An eye-catching domestic season in 2016 got him a Test call-up, and he showed his potential with a hundred and a half-century against Australia in his third Test. He also scored match-winning hundreds in Harare, and at home against West Indies and Pakistan, the latter two scores coming in the second innings, but more often than not, de Silva was playing with his back to the wall, in the midst of a collapse, like the hundred to save the Delhi Test in 2017 and 46 and 47 not out to help Sri Lanka survive longer in Christchurch in 2023. In the next Test in Wellington, he made 98 in the follow-on. What makes him even more valuable is his ability to chip in with part-time offspin and his reliable fielding in the slips. De Silva plays a similar role with the bat and ball in limited-overs as well - in the 2023 ODI World Cup Qualifier, his 93 helped Sri Lanka survive a scare against a determined Netherlands side.

In January 2024, he replaced Dimuth Karunaratne as Sri Lanka's Test captain.

De Silva first came to notice after topping the batting charts in the Super T20 Provincial Tournament in early 2016, hitting 234 runs at a strike rate of 133, in six innings. Months later, he was the star of Tamil Union's first victorious first-class campaign in 55 years, hitting 868 runs at 54.25, which featured a crucial fourth-innings 124 in the match that clinched his team the title. Incredibly, de Silva was also his club's most successful bowler that season, claiming 34 wickets at 14.23 with his part-time offbreaks.