Gareth Southgate vowed there is more to come from England at Euro 2020 after a narrow victory over the Czech Republic.
Raheem Sterling's early header was enough to seal a 1-0 win at Wembley to secure top spot in Group D.
England are yet to concede in the tournament - although have only scored twice through Sterling - and will face France, Germany, Portugal or Hungary in a last-16 tie at Wembley next Tuesday.
Despite what looks like a potentially tricky last-16 encounter, Southgate is pleased it will take place at Wembley.
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"There is more to come from us, definitely," Southgate said.
"We're not fluent but we have moments where we are a good side. We are still improving. We look difficult to play against.
"We haven't scored from a set play yet," he added. "I know people laugh about us only scoring from set plays but they are crucial in big matches and we have to get those nailed.
"We wanted to win the group, we wanted to stay at Wembley and we will wait and see who we play tomorrow.
It is great to be having more supporters in that is for sure. Who knows if that will be good or not. We wanted to win the group and stay at Wembley and we will wait to see who we play.
"They are different sorts of tests but there are a lot of good things we are doing.
"We have managed to get most of the squad into games, 90 minutes for Harry Maguire which was important, Hendo [Jordan Henderson] got 45 minutes which was a real step forward. There were a lot of positives for us."
Southgate on "important" minutes for Maguire and Henderson...
"It was a difficult call. Tyrone Mings has been an absolute colossus for us and again came into the game at an important moment and dealt really well with that as well.
"Harry Maguire has that presence and composure. His pass through to Kane in the first half was a fabulous ball through the lines and there aren't many defenders in world football who can do that. So, it was important for him to get those 90 minutes.
"It's obviously more difficult for Jordan Henderson because he's been out for so much longer. It was great to get him 45 minutes and he'll be better for that. That adds to our options in that area of the pitch."
Sterling hit a post inside two minutes before heading in Jack Grealish's cross to win it after 12 minutes.
Grealish was one of four changes and Southgate praised his players for adapting quickly after Mason Mount and Ben Chilwell were forced to self-isolate on Monday.
They came into close contact with Scotland's Billy Gilmour following Friday's 0-0 draw at Wembley. The midfielder subsequently tested positive for coronavirus and it forced Southgate into a late reshuffle.
"I thought we started really well, we were stable with the ball, we had worked on some of the stuff in training yesterday," he said.
"Credit to the players, some of the stuff we had to adjust without the ball as we had to change what we were doing overnight because of the different personnel.
"It was a huge credit to the players they were as stable without the ball as they were.
"We've played two opponents in the Croats and the Czechs who I think are playing at a very good level.
"And Scotland, which as an occasion and an experience for our players, especially the younger ones, was a quite unique and really important one, so these will be different games.
"We know world champions, European champions and Germany, who to me look like they're back on song. They've brought some very experienced players back in.
"So whoever we play, really, really tough opposition but we've sort of known that for 18 months. We've known the route through."
Jack produced a fabulous cross for the goal. We saw some of the interchanging positions of those forward players was really exciting,at the start of the game especially. I thought we tired a little bit, but we know that because one or two are a little it short of fitness.
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Southgate: 'Saka grabbed his opportunity'
With England already assured of a knockout spot, Gareth Southgate had said before kick-off "it's a great night for our attacking players to go and express themselves", and they did, especially Arsenal forward Bukayo Saka, who put in a man-of-the-match performance.
"We have been super impressed with Bukayo Saka throughout the month," Southgate said.
"He was excellent up at Middlesbrough and we have liked him with and without the ball. His receiving tonight under pressure was fantastic.
I thought Bukayo Saka was brilliant. I told him after the game that he got in the pockets of space, drove at people, he was direct and that's what you need. It's a credit to him.
"I can't speak highly enough of him. He's earned that opportunity. His performances in training since he joined this camp have been outstanding.
"We've talked about playing him in some of the previous matches and he earned that chance tonight and he's grabbed it. He was fabulous."
Bukayo Saka on his tournament bow...
“We played some really good football at times. Of course, with us already qualifying before the game we had a lot more freedom and a chance to express ourselves. I think that showed tonight and I am really happy with the performance by myself and by the team.
“The manager just told me to go and express myself how I have for my club this season. Sometimes that meant dropping in and driving at the opponents and I did that, got us up the pitch, and it was a good cross from Jack with Raheem in the right place at the right time again.”
Sterling: You have to play the best teams at some point
England goalscorer Raheem Sterling insists England must meet the knockout phase head-on after beating the Czech Republic to qualify for the last 16 as Group D winners.
"I think there are positives from the game," the Man City forward said. "We kept the ball better today. It gave us more attacking options. We got in the gaps really well, played some good football and got the goal we needed.
He added: "If you don't concede goals you win football matches. You just need to score at the other end. People were disappointed in the Scotland game a few days ago but we didn't concede. The most important thing was to win the group. It is tournament football and it will be difficult but we need to do what we are doing.
"At some point you have to face the best teams. It is about challenging yourselves."
Neville: I feel really confident about this England group
Sky Sports' Gary Neville talking to ITV:
"Job done, really professional. I will say it again, I don't think England are going to win this tournament by outplaying France, Germany, Portugal, Spain.
"I don't think we have the players to do that, I think we have good players, but I genuinely think we are going to win it by playing how are we are now, which is professional, keeping clean sheets, making sure that back is protected with those two lads in midfield. And then creating those individual moments of brilliance and we have got some players who can achieve that for us.
"Don't be surprised if we play Germany or France we go to five at the back because I think we may need more than four defenders against [Kylian] Mbappe, [Antoine] Griezmann and [Karim] Benzema.
"If you are playing against Germany we can comfortably go to wing backs, I don't rule anything out at this stage but I can't see that Gareth [Southgate] will play the same way against the Czech Republic as he would against France or Germany.
"I've been part of England teams where in the group stage, it has been an emotional roller coaster, a circus almost.
"If this was Germany, or another country, we would look at them and think, 'they look calm and in control.' We do not think that with England because we always want more, we want the brilliance and the 3-0 win.
"But I feel really confident about this group and I actually trust the manager and that he knows what he is doing with this group.
"Massive game next week, a giant of a game, but a week to prepare for it and I'm looking forward to it...."
Keane: 'Lots of pluses for efficient England'
Sky Sports' Roy Keane talking to ITV:
"They have been very efficient. Second half England did not have to be great, I was really disappointed with the Czech Republic's mentality to try and score a goal.
"But the bottom line is at this level, it is all about winning football matches, it is job done.
"Of course it is going to get tougher, the players know that, but the big pluses for Gareth tonight are another clean sheet, Maguire has had 90 minutes, Henderson has had 45.
"Gareth will be delighted."
Explained: Why Southgate is cautious | Is Grealish now a starter? | Foundations for future Scotland success?
Alice Piper is joined by Rob Dorsett and Pete Smith to discuss England's 1-0 win over Czech Republic at Wembley to finish top of Group D at Euro 2020. Jack Grealish finally gets a start for England - is he now here to stay? Why IS Gareth Southgate so cautious with the Three Lions? Plus: praise for Bukayo Saka and Raheem Sterling.
The panel also cover all England positions and talking points going into the last 16, and discuss how Southgate will approach the knockout stages.
And after Scotland's 3-1 defeat by Croatia at Hampden Park, Sky Sports News' Charles Paterson joins us to look back their campaign, and whether the foundations are in place for more success in the future.
Opta stats - Shot shy England get the job done
- England have topped their group at a European Championships for only the third time, also doing so at Euro 1996 and Euro 2012. With just two goals scored, they are the lowest-scoring side to ever finish top of a group at a Euros tournament.
- England have kept 15 clean sheets in their last 19 matches in all competitions, conceding only five goals. They have gone through a group stage at a major tournament without conceding for only the third time, also doing so at the 1966 World Cup and in the second group stage at the 1982 World Cup.
- England failed to attempt a single shot at goal in the second half of a match for the first time since October 2018 against Spain in a UEFA Nations League match. Their last effort at goal was a Harry Kane attempt in the 26th minute.
- Raheem Sterling has been directly involved in 20 goals in his last 19 matches for England (14 goals, 6 assists) and has ended on the winning side in all 12 matches when finding the net for the national team.
- Since his England debut last September, Jack Grealish has more assists than any other England player (3), despite only playing in nine of the Three Lions' 15 matches since then.
Finishing top of Group D means England will next play on Tuesday June 29 at 5pm at Wembley against the runners-up of Group F (either Portugal, France, Germany or Hungary).