Boris Becker says Alex Zverev's ambition to win his first ever Grand Slam will play a role in his semi-final match against Novak Djokovic.
Zverev, who lost to Dominic Thiem in the 2020 US Open final, is yet to win a Grand Slam in his professional career, while Djokovic is chasing a record 21st Slam title and the calendar Slam.
The two meet in Friday's semi-final and Boris Becker believes both players will have their own Slam records in mind when they go head-to-head inside Arthur Ashe Stadium.
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"You can't just watch the current tournament," he told Eurosport.
"Tennis doesn't work like that. You always have to consider the background as well.
"Novak Djokovic is playing for tennis history and sports history, Sascha Zverev is trying to win his first Grand Slam tournament. That will always play a role.
Nakedly, Zverev has only lost one set at this US Open, but all that is secondary when the two play each other in the semi-finals.
Djokovic's four-set win over Matteo Berrettini on Wednesday night means the 34-year-old has dropped the first set in the last three matches he has played en route to the semi-finals.
Becker, who used to coach the world number one, says it can take time for Djokovic to get going in a match before pulling out the victory he needs.
"Djokovic has a different game," he added.
"He unnerves you about the length of the match. On the one hand, his opponents were very strong at the beginning, but on the other hand, Djokovic doesn't let that bother him.
"He really gets going after one and a half or two hours and then finishes the matches very strongly. It's almost a strategy of Djokovic's to unnerve his opponents first and then beat them."
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