West Indies scrambled a pulsating one-wicket victory over Pakistan on Sunday as the visitors self-destructed in the final session of the fourth day when on course to take the first Test of the two-match series at Sabina Park.

Defending a modest target of 168 after they were dismissed in the morning session for 103, Shaheen Shah Afridi led the attack with figures of four for 50 in reducing the home side to 114 for seven at tea with only wicketkeeper-batsman Joshua da Silva and the tailenders left.

However, in scenes reminiscent of a similar one-wicket loss in the deciding Test of the 2000 series in Antigua, the Pakistanis lost the discipline in their bowling and composure in the field.

Three catches were missed to allow Kemar Roach and last man Jayden Seales to take their team to the target with a last-wicket partnership of 17. Roach, who was dropped twice, hit the winning runs off Hasan Ali to finish unbeaten on 30.

Ironically, it was Hasan who missed a straightforward catch at deep square-leg off Shaheen which allowed Roach to eventually complete the job at the end alongside a jubilant Seales.

Seales was named man of the match for his match haul of eight for 125 which included five for 55 in the second innings.

For the fast bowler, who is less than a month away from his 20th birthday, it was an historic achievement when he mopped up the Pakistan tail with the last three wickets to become the youngest-ever to take five wickets in a Test innings for the West Indies.

"I just decided to take it step by step, run by run," said a relieved Roach minutes after completely what looked an unlikely task when he joined da Silva at the start of play after tea. "This is easily the most important innings I have ever played and credit to Jayden as well for holding on with me at the end and for his five-wicket haul today because he s someone really special as a young fast bowler."

Pakistan captain Babar Azam did well to hide his disappointment but could not avoid referencing the obvious costly errors when it mattered most. "This is the beauty of Test cricket. Our bowlers were really good especially Shaheen and Abbas," said the skipper, omitting to mention the three wickets taken by Hasan in the push for victory.

"Had we taken those catches the result could have been different."