The West Indies seamers made early inroads into the Sri Lankan line-up to leave them staggering at 34 for 3 but captain Kumar Sangakkara (25) and Thilan Samaraweera (26) added a 50-run unbroken stand to steady the home ship, surviving a testing spell of fast bowling to take the hosts to the close of play.
Only eight balls were possible in the final session before play was halted.
Having won the toss, Sangakkara’s decision to bat was immediately put under the spotlight as pace duo Roach and Darren Sammy extracted movement and bounce from the newly laid surface at the R. Premadasa Stadium.
Roach claimed his first wicket in the fifth over, bowling Tillakaratne Dilshan for four with the total standing at just 10.
He struck again in the 13th over to have Tharanga Paranavitana caught by Dwayne Bravo at second slip for 16.
In the following over, Sammy got in on the action, bowling Mahela Jayawardene for just two to leave the home side reeling.
However, Sangakkara and Samaraweera provided greater resistance and capitalised on easier conditions to add 50 between them before bad light ended the day’s play.