England coach Trevor Bayliss was in awe of Alastair Cook's powers of concentration during his man-of-the-match, marathon innings of 263 against Pakistan in the first Test.
Captain Cook batted for almost 14 hours, the longest ever by an Englishman, to put his team into a position from which they almost pulled off an astonishing victory at Abu Dhabi's Zayed Cricket Stadium.
It was only gathering dusk that stopped them going 1-0 up with two to play, the opening match of three ended by bad light with England on 74 for four - chasing 99, with eight more scheduled overs left.
Debutant Adil Rashid was the driving force with five for 64 on the final day as Pakistan were bowled out for 173 - but it was Cook's determination which dragged England back into contention, after their hosts had piled up 523 for eight declared in the first innings.
Asked for his reaction while Cook was batting, and that of the players in the dressing room, Bayliss made it clear they are all full of admiration.
"(It's) one of awe, I think," said the Australian.
"It is just an unbelievable will to concentrate for that long ... an unbelievable effort."
Cook has made tireless batting his speciality, often in Asian conditions, and Bayliss added: "There are some very good players in both teams ... but for someone to bat like that from the top of the innings - I think he spent over four days on the field - his powers of concentration are just superb.
"It's not the first time he's done it, so it really wasn't a surprise he was able to bat that long."
Cook did not need to enhance his reputation among team-mates who already have huge respect for him.
"I don't think it changes his standing in the team at all, because I think the rest of the players already have a very high opinion of their captain," said Bayliss.
"He's very well-respected. It was just another sign to the players that he is an extremely good player, a hard worker - and a sign to them how hard they've got to work.
"If they can work just as hard as him, this team's got some good times in front of it."
Among them, Rashid produced a resilient performance - having recorded figures of nought for 163 in the first innings, on a very slow pitch.
Bayliss believes the experience could be the making of the leg-spinner.
"Certainly," he said. "He did exactly what we thought he was more than capable of doing.
"In the first innings, it was very difficult to bowl spin on that wicket - as I think the four or five spinners in the match found.
"But spinners, especially leg-spinners, really come into their own on that last day - and he showed the quality he has got."
Bayliss had no qualms with rules which forced the players off in fading light, but agreed with many that the playing surface was too slow.
He said: "I'd like to see a little bit more pace in the wicket - not just for the pace bowlers but the batters and also the spinners.
"Even they would enjoy a little bit more pace, a bit faster spin.
"If the wicket was just a little bit quicker, it would make for a lot better game to watch."