USMAN Khawaja drastically ramped up his fitness regimen during the off-season and in the first Test against Pakistan, the results were there for all to see.

The 31-year-old - now seven kilograms lighter than he was in April - grinded out 141 runs off 302 balls in the unrelenting Dubai heat to claim an unlikely draw for Australia.

Combined with his first-innings 85, and two long stints in the field, Khawaja spent more than 27 hours of play in the middle.

About 13 hours of which were at the crease alone, as temperatures stayed in the high 30s all match.

“That first innings was as tough as any innings I’ve played,” Khawaja told reporters. “I came off the field with sweat through my shirt. My shirt was drenched and pants were drenched. That took it out of me a fair bit.”

Speaking of the final day’s play, he added: “I was feeling pretty good for most of it until we got to the second session with one hour left before tea, then I was withering.

“I was just asking for God to get the sun down so we could get some shade.”

Khawaja ended the day with his first century in Asia, and the highest ever fourth-innings score by a non-Asian batsman on the continent.

It’s a feat he couldn’t have accomplished without shedding weight during the off-season, Fox Cricket’s Brett Lee said during the tea break.

“He’s fit now ... we all joke about it, but he couldn’t have done that if he wasn’t fit,” he said.

Fellow former Test star Mark Waugh added: “It doesn’t even look like he’s sweating.

“You can’t bat any better than that. His concentration is great in the heat, his fitness levels have been outstanding.”