West Indies overcame a career-best one-day score from Misbah ul-Haq, and some hostile Pakistan fast bowling, to register a two-wicket win at the Oval.
The two Group B rivals served up a low-scoring treat in the second match of the ICC Champions Trophy, the men from the Caribbean bowling out their opponents for 170 before squeezing over the line with 56 balls to spare.
Chris Gayle (39), Marlon Samuels and Kieron Pollard, who both made 30, hit useful contributions before tail-ender Kemar Roach struck the winning blow, meaning Misbah's superb knock of 96 not out was to be in a losing cause.
The Pakistan skipper did all he could to try and drag his side to a competitive total after they had plummeted to 15-3 after 37 deliveries.
Roach removed Mohammad Hafeez, Imran Farhat and Asad Shafiq in a devastating opening spell; he also thought he had seen the back of Misbah when he edged behind to Ramdin, only for the decision to be overturned after it became clear the wicketkeeper had grounded the ball.
The let-off allowed the right-hander to combine with Nasir Jamshed - the only other Pakistan player to reach double figures - in a 90-run stand for the fourth wicket that appeared to be repairing much of the early damage.
However, once Jamshed hit Sunil Narine straight out to Ravi Rampaul to depart for 50, the innings subsided again. The same bowler removed Shoaib Malik for a golden duck and Kamran Akmal (two) as he claimed three wickets in 10 balls.
With his team's innings in tatters at 138-9, Misbah had no choice but to open his shoulders. He hit two sixes to go past his previous one-day best of 93 not out but missed out on the chance to reach three figures when last-man Mohammad Irfan was caught by Bravo at mid-wicket off Rampaul's bowling.
The giant Irfan did his best to make amends with two early wickets with the ball, though at 78-2 the West Indies seemed to be coasting home.
Yet a spell of three wickets for 16 runs, including the prized scalp of Gayle, who was bowled by Saeed Ajmal (2-38), set up a nervy finish. Pollard and Dwayne Bravo carried the total to 137-5 until both perished in quick succession, leaving Ramdin (11 not out) and the tail to finish the job off.
Narine added a couple of crucial boundaries to ease the nerves in his own dressing room and although he was caught behind to Irfan (3-32) trying to find the fence again, Roach held his nerve under pressure.