Zverev has won four of his six matches against Sinner, although the Italian prevailed in a three-hour epic last year in the Cincinnati Masters semi-finals.
โFirst of all, itโs going to be mental,โ Sinner said of the final.
โItโs going to be a tough match for both of us. Itโs going to be physical, for sure.
โHe played some incredible tennis to go to the final. Itโs tough to say who is the favourite, in a way, because everything can happen.โ
There was drama during the third set on Friday night as the explosive Sheltonโs level soared again and Sinnerโs legs were visibly wobbling at the other end.
It was a surprising turn of events, given the top seed had seemingly assumed total control in a dominant second set.
The left-handed Shelton has power in spades and the ability to blast outrageous winners, which makes him a dangerous opponent.
Even then, the American could not break through.
Three break points came and went across Sinnerโs opening two service games of the third set, and his cramping worsened in the fifth game as Shelton tried to edge 3-2 ahead.
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But Shelton double-faulted before dumping a forehand into the net to give Sinner the lead for good.
After a leg massage and some pickle juice, Sinner cruised to the finish line.
Shelton was left to rue his missed chances, after twice being up a break in a 71-minute opening set where his hyper-aggressive approach rattled his rival on occasion.
The downside was unforced errors flowed in great numbers, and he already had 27 by the end of the first set, including five in a lopsided tie-breaker where he swiftly fell 5-0 behind.
Shelton had 55 of them by matchโs end, more than double as many as Sinnerโs 26, while hitting only four more winners.
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โHonestly, Iโm really disappointed. You know going into the match that playing Jannik is a tough ask, Shelton said.
โIโve made my living on tour so far serving out sets, and having two set points on my serve, serving at 6-5, I feel like [it is] uncharacteristic for me not to come through and win that.
โObviously, youโre playing the No.1 player in the world; the chances, the windows are always small. Sometimes you miss your window, and the guy steps up his level, starts making a lot more first serves, [and] playing better. The break chances donโt come as often.
โI thought I did some things well out there today โฆ [but it was] probably one of my worst serving days in this tournament, which is disappointing, now being six matches in.โ
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