MULTAN, Pakistan: Joe Root said there are "many more runs to get" after he surpassed Alastair Cook to become England's greatest Test match run-maker on Wednesday.
Root moved past Cook's 12,472 runs when he drove Aamer Jamal for a boundary to reach 71 on his way to a brilliant 176 not out on the third day of the first Test against Pakistan.
The 33-year-old batted through the day in the heat and fought cramp to register his 35th Test century, taking England to 492-3 and within 64 runs of Pakistan's first innings after an unbeaten 243-run stand with Harry Brook.
"(I feel) tired, more than anything. It's been a long day," said Root.
"I'm obviously proud, but still feel there's plenty more left to do and many more runs to get.
"I'm sure I'll look back at it at some point when I'm finished and be very proud of it."
Root also put on century partnerships with Zak Crawley (78) and Ben Duckett (84), who came in at four after hurting his thumb while taking a catch to wrap up Pakistan's innings late on the second day.
He and Brook (141 not out) then set about putting England in a strong position after two days of toil in the field, as Pakistan struggled for answers with the ball on a flat wicket in Multan.
"I think more than anything just the way we played today as a team is what stands out," said Root.
"We've still got an opportunity to win the game, which is really exciting. Hopefully we can kick on tomorrow."
Duckett, who combined with Root to add 136 for the third wicket, hailed the achievements of his team-mate.
"He (Root) is one of the greats of the game and certainly a great of English cricket," said Duckett.
"He is extremely humble and those things don't bother him and he wants to play for England as long as he can."
With 12,578 runs, Root is now fifth in the list of all-time Test run-scorers. India's Sachin Tendulkar sits at the top of the pile on 15,921.
"It's just a pleasure to share the dressing room with him," said Duckett. "He is probably still working as hard as he ever has, always grinding away in the nets.
"We make jokes that he says he is out of form and he is still getting hundreds, so it's probably a good place to be in."
Duckett revealed Root was fully aware of the milestone and backed him to set more records.
"He 100% was aware (of the record) but I think he made out that he didn't have any idea," said Duckett. "I did not know so I asked him and he told me, so he definitely knew."
"When he is in good form, he cashes in and scores big and I hope it continues," added Duckett.
"If he stays fit and stays on the park there is no reason why he can't break more records. He is an incredible player and there are no signs of his form dipping."
England batting coach Marcus Trescothick, a former opener who played 76 Tests, expressed his pride at Root's accomplishments.
"We're lucky enough to sit and watch history being made," Trescothick told Sky Sports. "The way he goes about it, the work he puts in and continues to strive for greatness all the time.
"He's been superb and think will continue to be superb for a number of years yet."
Pakistan captain Shan Masood, who made 151 for the hosts in their first innings total of 556, tipped Root to eventually go past Tendulkar.
"Congratulations to Joe, but I personally want to hold this congratulations till he becomes the leading Test run-getter, which I'm sure he'll achieve," said Masood.
"He's not only the best batsman I've come across in my life but one of the best human beings also."