Dimuth Karunaratne and Nishan Madushka both hit centuries as they amassed a record Sri Lankan opening stand in Galle of 228 in the second test against Ireland on Wednesday.
The hosts were 357 for one at the close, still 135 runs behind but with nine wickets in hand.
Madushka was unbeaten on 149 at stumps, alongside Kusal Mendis, approaching a century of his own on 83, after Karunaratne departed for 115 – the only wicket to fall on the third day of the match.
The first test ended inside three days with Sri Lanka's spinners dominating, but the pitch in the second encounter has offered the spinners little assistance and the batsmen dominated proceedings.
Captain Karunaratne reached the 16th century of his test career, and his second consecutive ton, in just 116 balls.
But the left-hander mistimed a pull shot off Curtis Campher and was caught at deep fine leg in the last over before lunch, two balls after he was hit on the helmet.
Madushka had already brought up his maiden test century, pulling a Harry Tector full toss for six.
Their 228 was a record Sri Lankan opening partnership at the ground, eclipsing the 193 between Marvan Atapattu and Sanath Jayasuriya against South Africa in 2000.
Mendis and Madushka continued the run-fest, with the No 3 racing to 83 off 96 balls with seven fours and five sixes, including three in a row off debutant left-arm spinner Matthew Humphreys, who was rapidly taken off the attack.
Bad light interrupted play before tea, before the rains came down and it was called off for the day.
Play will resume 15 minutes early on the final two days to make up for lost time.
Sri Lanka lead the two-match series 1-0.
Report Day 1Report Day 2
SRI LANKA: Dimuth Karunaratne (captain), Nishan Madushka, Kusal Mendis, Angelo Mathews, Dinesh Chandimal, Dhananjaya de Silva, Sadeera Samarawickrama (wicketkeeper), Ramesh Mendis, Prabath Jayasuriya, Vishwa Fernando, Asitha Fernando.
IRELAND: James McCollum, Peter Moor, Paul Stirling, Andy Balbirnie (captain), Harry Tector, Curtis Campher, Lorcan Tucker (wicketkeeper), Andy McBrine, Graham Hume, Matthew Humphreys, Ben White.