Sri Lanka 247 for 6 (Karunaratne 110, de Silva 64, Mumba 4-50 ) and 537 lead Zimbabwe 373 by 411 runs
Scorecard and ball-by-ball details
Dimuth Karunaratne struck his second fifty-plus score of the match and his first Test century in a year to bump up Sri Lanka's lead to 411 before rain wiped out almost all of the third session. His 94-run stand for the fifth wicket with Dhananjaya de Silva, which came at 4.47 runs an over, on a surface with variable bounce, countered debutant fast bowler Carl Mumba's strikes and helped Sri Lanka re-establish their dominance in Harare.
With a thunderstorm predicted for Wednesday, Sri Lanka might consider an overnight declaration to force a result.
In the absence of Angelo Mathews and Dinesh Chandimal, Karunaratne was the most experienced batsman in the side. Yet, he was under pressure going into the Zimbabwe tour, having bagged eight single-digit scores in his last 12 innings. His slump could have been extended to 10 single-digit scores in 14 innings had Zimbabwe hung onto their chances. He, however, rode his luck, and followed his chancy 56 in the first innings with a more secure century in the second.
He was dropped on 5 by Brian Chari, diving to his left at extra cover, on the fourth morning, but other than that Karunaratne seemed in control. He had joined forces with de Silva after Mumba had struck either side of the lunch break. Kusal Mendis skied a leading edge to the right of mid-on where it was pouched, while Upul Tharanga drove away from the body and nicked behind. With Sri Lanka at 117 for 4, Zimbabwe sensed an opening, but the visitors slammed the doors on them.
De Silva was fluent from the outset, punching and flicking with typical insouciance. The shot of his knock, however, was the check-driven straight four off a Chris Mpofu offcutter in 39th over. He further upped the scoring rate when he swatted Greme Cremer for two boundaries in the 48th over. By then the lead was 345.
De Silva brought up his fifty off 65 balls. His fluency probably rubbed off on Karunaratne, who grew comfortable in the second session, after being put through a stern examination in the channel outside off in the morning. Later when the seamers dug the ball short and aimed to cramp him up, he did well to ride the bounce and pull behind square. He reached the three-figure mark by nudging Cremer to square leg, and it was relief rather than raucous celebration for the opener.
Karunaratne and De Silva then exited either side of tea before rain allowed only 23 balls. Karunaratne chipped an offcutter back to Mpofu, while de Silva jabbed a rising delivery to point to give Mumba his fourth wicket.
At the end of the third day's play, Zimbabwe's captain Cremer outlined their plan: pin down the flow of runs with tight bowling and in-out fields. Mumba reaped the reward for relentlessly probing away on a fourth-stump line - or occasionally a set of stumps outside off - when Kaushal Silva played away from the body and inside-edged a drive to leg stump for 7 off 20 balls.
Kusal Perera, batting at No. 3, then creamed his second delivery to the right of extra cover for four in the 10th over, also the first boundary of the innings. Karunaratne, meanwhile, got into his groove with a brace of late-cut fours. They put on 55 in 12.5 overs, before part-time offspinner Malcolm Waller struck in his second over to have Perera caught at slip for 17. Waller had looped it up on the rough and got it to spin away to find the outside edge, which was snaffled by Hamilton Masakadza diving to his left.
Karunaratne and de Silva, however, foiled Cremer's plans as the day progressed. Considering the rain threat, Sri Lanka's plans could be foiled too.