On Tuesday, he passed 600 runs for the series and 5,000 career Test runs.
Sydney: Opener Alastair Cook's prolific form in the Ashes series has come as no surprise to his team mates, according to England opening bowler James Anderson.
Fighting to retain his place in the team until his century against Pakistan at the Oval in August, the 25-year-old left-hander scored 67, 235 and 148 in the first two Tests.
On Tuesday, he passed 600 runs for the series and 5,000 career Test runs on his way to an unbeaten 61 in England's first innings in the final Test.
"He's been fantastic," said Anderson. "Considering people were questioning his spot during the summer, I think he's shown exactly what sort of player he is.
"He's got a huge talent, there was no doubt in our team that he was going to perform here."
The transformation of Cook's fortunes in Ashes matches is illustrated by an average of 26.1 against Australia before the series compared to the average of 127.6 he enjoys in the current series.
Cook has always had to work hard on his game, which Anderson believes makes his performances more admirable than those of more naturally gifted players such as his England team mate Kevin Pietersen.
"He's probably more talented than a KP," Anderson added. "KP finds it so easy to play, so naturally gifted with the shots he's got.
"Cookie's not got that. He relies on the shots he has got and he relies on his mental toughness to get him through.
"It's just shown how talented he is, this trip."
While Australia's top order has floundered so far in the series, England's has been the foundation for their success, in particular the opening combination of Cook and skipper Andrew Strauss.
"It's been a massive contribution to get off to a good starts," Anderson said. "It just settles the dressing room and gives everyone a lot of confidence."
Anderson, who will resume on one alongside Cook on Wednesday after coming in as nightwatchman, said the openers had grabbed the initiative back for England after Australia's tailend had wrested it from them.
By contrast to Cook's diligence, Strauss made a conscious effort to score quickly with a 49-ball half century before he was bowled for 60.
"Straussy's quite a positive batsman," said Anderson. "He puts away bad balls and that's what he did today."