Kotmask dug deep to cling on to victory in the Chatteris Fen Juvenile Hurdle at Huntingdon.
Trained by Gary Moore and ridden by his son Jamie, Kotmask was having just his second British outing having won by 12 lengths on his debut for the yard at Fontwell last month.
Sent off the 6/5 favourite, Moore was quick to seize the initiative, with Genuflex the only rival to try to take him on in front.
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The pair had a couple of lengths in hand over the rest of the field turning for home, but Genuflex was starting to feel the pinch, allowing Kotmask to move into a clear lead with two hurdles to jump.
However, Collingham was making strides on the far side, challenging at the final obstacle before appearing to shade the lead on the run to the line.
But Kotmask was extremely game in the finish, just edging back in front in the shadow of the post to claim a head verdict, with Genuflex plugging on for third.
Paddy Power offer 25/1 about Kotmask for the Boodles Juvenile Handicap Hurdle at the Cheltenham Festival.
Owner Gary Robinson said: "I got a little worried coming to the finish, but he is a great horse with a lovely temperament. He has done well for us today and I'm really pleased.
"He did a good job at Fontwell when he ran out an easy winner. I was a little bit worried about the ground being much harder, but he has done it and a win is a win.
"I'd love to see him at Cheltenham in March and hopefully he will be there. Whether that is the Triumph Hurdle or the Fred Winter (the Boodles), it would be great. I think more so at the moment it would be the Fred Winter.
"This is the second horse I've had with Gary as I bought a horse called Yorksea and he has been doing OK and he came second at Cheltenham. To win at Cheltenham is the ultimate dream and it doesn't matter what the race is."
While Robinson is keen to go to Cheltenham, his rider was more cautious.
Moore said: "He showed a lot of guts and that was only his third ever start. He jumps well - he takes a little bit too long in the air but that will get ironed out in due course.
"I don't know where we go next as I don't know what dad has got planned for him. I don't worry about Fred Winters and Triumphs as there are plenty of other races.
"There are handicaps at Ascot and Newbury at the end of the season and they are other options for us."
The Moore team made it a double in the closing Racing TV "Newcomers" National Hunt Flat Race as Odin's Quest (15/8) prevailed by two and three-quarter lengths, giving the winning jockey his 50th success of the campaign.
Holly Hartingo (10/11 favourite) made it two wins in as many starts for Alastair Ralph in the Racing TV Mares' Novices' Hurdle.
Successful at Ludlow last month, Jonathan Burke's mount cruised home by five lengths from Hillfinch.
Jack Martin secured the first win of his career aboard the Philip Hobbs-trainer Alberic (5/4 favourite) in the Racing TV Conditional Jockeys' Handicap Hurdle, while Freres D'Armes (4/5) was another for favourite-backers in the EBF "National Hunt" Novices' Hurdle.
Martin said: "It is amazing and brilliant. I don't think it has really sunk in yet.
"I knew he was favourite and a lot of people said 'don't let pressure get to your head and ride your race'. I probably would have liked to have been handier and I should have been.
"Where I was he was happy and he travelled away. He wanted a bit of daylight turning in and he got that today and stuck his head out to the line which is the main thing.
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"This is my fourth season with the guv'nor (Philip Hobbs). I've been an amateur for three seasons and my dad Paul was an ex-professional jockey.
"I was based in Ireland, but I didn't get much. I went to Philip Hobbs and I spoke to my cousin Brian Hughes and he said, 'keep your head down and keep grafting'.
"This is a dream come true and hopefully I will get plenty more before the end of the season."
Freddy Fanatapan (100/30) was another market leader to strike gold in the Racing TV Handicap Chase, but Our Power (11/4) proved too good for Dorking Lad, the favourite for the Racing TV Novices' Limited Handicap Chase.