Their partnership - 577 balls in - is worth 246. It is easily Sri Lanka's best against New Zealand, and has allowed the visitors to go into the fifth day of an intriguing Test with a fighting chance of securing a draw. They are still 37 runs away from making New Zealand bat again, but will be buoyed no doubt by the weather forecast, which suggests rain will arrive around mid-day, if not before.
Mathews was in a dogfight virtually the entire time he was at the crease, hit by balls last night and in the first session on Tuesday, defending with astounding stoicism - but Mendis played a more attractive innings, at least in the morning. While Mathews was struggling to work himself into the innings, playing and missing, and failing to get out of the way of some of New Zealand's many bouncers, Mendis struck sublime straight boundaries to prevent the quicks from settling, and made sure to climb into a few commanding pull shots as well.
There were a few occasions through the day when Mendis slowed down, and Mathews took the scoring burden upon himself, but after lunch, both had basically decided that nothing New Zealand sent their way - not another spell of Neil Wagner bodyline, not another spell of Tim Southee probing outside off, not Ajaz Patel's disciplined lines and lengths - were going to shake them out of their calm.
Mathews has batted like this before, of course, and has played several match-saving innings in his career, though it has been a while since the last one. For Mendis, this was a new sort of innings entirely - one which, at least since after the lunch break, was focused largely around his defence. Fittingly, the pair were separated only by a run at the end of the day. Mathews had 117 off 293 balls; Mendis 116 off 284. The younger partner had led Mathews for much of the day, but Mathews took more of the strike in the third session.
Central to both batsmen's survival was their judgement of length. Both Wagner and Southee repeatedly went to the short ball attack, with virtually no seam movement on offer from this surface now. Mathews had the tougher time in the morning, copping blows on the bicep and the chest. But soon enough, he was ducking and weaving expertly, and on the occasions that he did play a cross bat shot, he uniformly ensured he had rolled his wrists over it, and hit it towards the ground. Although Mathews was always striking at less than 50, he never seemed bogged down, finding shots to get himself off strike regularly enough. Mendis followed Mathews' lead with the short ball for much of the day, crouching beneath plenty, to let them fly harmlessly over the shoulder.
With their seamers unable to break the overnight stand, New Zealand looked to left-arm spinner Ajaz Patel, who bowled unchanged through the middle session, but here again, the batsmen had his measure. Occasionally, the ball turned off the straight to beat the bat, but this didn't happen often enough to comprise a serious problem for Mendis and Mathews.
Interestingly, Mendis didn't venture the sweep - his favourite shot - choosing instead to knock Patel into the open spaces from an upright position, perhaps because there wasn't much turn on offer anyway. So perfect were these two in defence, that through the course of the day, there wasn't so much as a strong lbw or caught behind appeal. The likeliest form of dismissal seemed a run out - with two batting miscommunications leading to several tense moments mid-pitch, through the latter half of the day.
Mendis had gone to tea on 98 and was the first to his century soon after resumption. He raised his bat and held up six fingers to signal his sixth ton. Mathews, though, provided by far the more colourful celebration, in the final hour of play, whipping a four to wide long-on to reach triple figures for the first time in over a year, before dropping to the ground and reeling off 10 push-ups. This was the latest in a string of gestures to the dressing room, and to coach Chandika Hathurusingha in particular, about his fitness. Mathews had been hurt by his axing from the limited-overs teams in September over fitness and running issues.
Sri Lanka remain vulnerable in this Test - a collapse on day five could still lead to a big New Zealand victory. But by getting through day four unscathed, they have showed they have the ability to compete, and the hunger to stay in the fight.

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