West Indies closed the third day of the opening Test against Sri Lanka on 269-9, still eight runs short of avoiding the follow-on.
Ramnaresh Sarwan marked his return from injury with an elegant innings of 80 but was given little support from his top-order colleagues.
Sri Lanka off-spinner Muttiah Muralitharan claimed three of the eight wickets to fall on day three at Providence Stadium, Guyana to leave the hosts facing a battle for survival.
West Indies lost three wickets during the morning session to slump from 29-1 to 107-4.
Left-arm seamer Thilan Thushara (2-59), playing in his second Test almost five years after his debut, had both Devon Smith (14) and Marlon Samuels (5) caught behind.
And Muralitharan followed up with the key wicket of Shivnarine Chanderpaul (23), caught from a spooned drive by Malinda Warnapura at short cover, to end a fourth-wicket partnership of 41 with Sarwan.
Sarwan, on his return to the Test arena for the first time since injuring his shoulder on last year's tour of England, stood firm to reach his half-century from 99 balls.
But West Indies' hopes of avoiding the follow-on looked bleak when Dwayne Bravo (8) was trapped lbw by Muralitharan shortly after lunch to reduce the hosts to 109-5.
Sarwan and Ryan Hinds added 53 off 65 balls to raise hopes of reaching the follow-on target of 277.
But Sarwan departed for 80 to Chaminda Vaas (3-45) off an edged drive that was expertly held by wicketkeeper Prasanna Jayawardene standing up at the stumps.
Hinds (37), Denesh Ramdin (38) and Suliemann Benn (28) each briefly held up the tourists during the final session without going on to make the substantial contribution the situation required.
And although last-wicket pair Jerome Taylor (22no) and Daren Powell (6no) survived almost 10 overs at the end of the day, West Indies still need them to eke out a further eight runs tomorrow to avoid the follow-on.