This has been a week in which Test cricket's merits have been shown in vastly contrasting lights. On the one hand a shocking contest has dribbled to a conclusion in Colombo, with 17 wickets falling in five days at the SSC, including 10 batsmen passing fifty - five of them for a hundred, two of them for a double. At Trent Bridge, on the other hand, consecutive days have passed in which 15 and 13 wickets have tumbled, and all told, 18 batsmen to date have been dismissed in single figures.

There's no question whatsoever which of the two contests has been the most compelling, not even at a stage of the Trent Bridge game when only one team has the slightest hope of victory. At 15 for 3 overnight, Ladbrokes are offering odds of 2-1 for England to wrap up victory before lunch on the fourth day, but even if they do so, the effort that Matt Prior put into today's magnificent unbeaten century will not be compromised by the eventual gulf between the sides.

Prior has had a rough time of it of late. Through no great fault of his own, he's been pushed to the margins of England's wider squad planning, with Craig Kieswetter's emergence leaving him in limbo in the limited-overs set-up. No-one in their right mind has seriously pedalled the notion that his Test berth is in the same sort of jeopardy, and yet, such is the nature of the England wicketkeeping position, the doubts require almost daily dispersal.

Therefore, a superbly combative 102 not out, forged from a position of peril at 72 for 5, was quite some statement of intent. It was Prior's third hundred in 32 Tests, and his first since Trinidad in March 2009, but by the close of play, his satisfaction derived from the manner in which he'd transformed his team's position, rather than the fact he'd logged another statistic in his record-book.

"I'm not a huge stats watcher, or a stat man," he said. "I got a 93 in my last Test [against Bangladesh at Old Trafford], so it doesn't feel that long ago that I contributed to the team. Whether it was important to show what I could do, I don't know, but I went in in a position when the team needed me to get stuck in, and getting runs for the team was the important bit."

In fact, a century could hardly have been further from Prior's thoughts for much of his innings, which began in the midst of yet another of Pakistan's inspired bursts with the ball, as Umar Gul swiped three wickets in four overs to leave his team dreaming of an attainable run-chase. His most immediate concern was to atone for his part in the run-out of Eoin Morgan, and by the time he was joined by the No. 11, Steven Finn, he had a long, long way still to travel, on 63 not out.

"I don't know what happened there," he said of the Morgan mix-up. "At that time, too many risky runs and singles wasn't the best idea, so it was a bit of miscommunication really. I didn't hear him say yes, he didn't hear me say no, and we ended up looking at each other, with him halfway down the wicket and me thinking: 'Oh my gosh, it's happened again'. It is very disappointing to be involved in a run-out at any stage, especially when it involves arguably your best player of the moment, so I thought I'd best knuckle down here!"

Knuckle down he did, with Finn proving to be the most obdurate of allies. While his stonewalling prowess came as a surprise and a delight to a packed Trent Bridge crowd who cheered every step towards England's eventual declaration, Prior himself had no doubt whatsoever about Finn's ability, having witnessed it at close quarters during a rare Championship appearance for Sussex against Middlesex at Uxbridge last week. With Morgan at the other end, Finn had blocked out 35 dot-balls in a 12-over partnership, to save the game with only two wickets standing.

"It was thoroughly annoying," Prior recalled. "But as he walked to the wicket today, I said something along the lines of 'Same again today please mate!' He did such a fantastic job, not only in the way he played, but what he contributed to the partnership in between overs, in terms of gameplans and all those things. He did all that was expected of him, and more."

Regardless of his faith in his team-mate, Prior still had to endure some nervy moments at the non-striker's end, as he crept through the nineties - single by single - with many of his shots coming from the first ball of an over. "My gameplan was to look for twos and fours, but every run counted, I felt, especially when Finny came up to me to say he felt confident at holding up an end. It got a bit frustrating at the end because I wasn't quite hitting the gaps, but I didn't want to turn singles down."

That failure to work the angles is the precise reason why Prior's spot in the one-day side has been passed across to Kieswetter, who may lack the subtlety of, say, Morgan, but tends to find the boundaries with a lot of bottom hand. In terms of pure batsmanship, however, there's no comparison between the two men whatsoever. Kieswetter has time on his side and a talent to cultivate, but as a battler who can be backed to produce on demand, Prior's place for the Ashes is utterly non-negotiable.

"I've batted at six with success, and I've batted at seven, and I feel well placed to do the role in each, as long as we have the right balanced team to win the Test match," he said. "International cricket is all about pressure and how you respond to it. I've not played a day for England as a batsman-keeper that's not been under pressure, but I enjoy and thrive on it, and I embrace it rather than get nervous about it."