Alexander Zverev is into the second round of the Australian Open but needed four sets as he went on to win (8)6-7 7-6(4) 6-3 6-2 against unseeded American Marcos Giron.
Giron began really well on Margaret Court Arena against the 2020 semi-finalist, pushing Zverev into a tie-break and the unseeded American converted his fifth set point in the dramatic shoot-out to take a surprise lead 7-6(8).
Zverev was serving for the second set but Giron broke him to make it 5-4, prompting the German player to smash his racket in frustration and pick up a code violation.
The 23-year-old recovered and came out on top in the tie-break decider, winning it 7-4 before sealing the third in just 23 minutes as his serving improved.
The final set was also relatively straightforward for the highly-rated German who is chasing his first ever Grand Slam title. He broke a tiring Giron in the fourth game and comfortably held his serve en route to victory.
Zverev will face either Taro Daniel or Maxime Cressy in the second round.
'World class' - Zverev wins epic rally with stunning backhand winner
Zverev: I didn't play my best
"I'm extremely happy to be back here and playing because you never know with Covid right now," Zverev said post-match.
"I think all of the players want to thank Australia generally for letting us in. It's going to be an incredible two weeks and I hope everyone will enjoy it.
"He [Giron] played incredible. I think he knew that on the big stage against a top ten player he has to come out firing and give his best. He had me on the ropes and especially in the second set in the tie-break that could go either way. I'm happy to get through.
"I didn't play my best but I'm through to the second round and that's what's most important right now.
The first round of a slam is never easy especially as two days ago I spent three hours on court against Medvedev and Novak [Djokovic] so that's not easy. My body was a bit tired but this is a slam, you don't have easy opponents and sometimes that's what you have to do, win matches.
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