Lucky number seven! Jannik Sinner beats Alexander Zverev again in Miami semifinals

Jannik Sinner's mastery of Alexander Zverev continued in the semifinals of the Miami Open on Friday, with the world No. 2 recording a 6-3, 7-6(4) win in the semifinals.

Two streaks continued for Sinner with the 1 hour and 53-minute triumph. He has now won his last 16 matches at ATP Masters 1000 events, and seven straight matches against Zverev. He hasn't lost a set in his 1000-level winning streak, and will face Jiri Leheck on Sunday in an attempt to become the first match since Roger Federer in 2017 to complete the Sunshine Double of winning Indian Wells and Miami back-to-back.

Read more: Jiri Lehecka routs Arthur Fils in Miami to reach first Masters 1000 final without dropping serve

Sinner also defeated Zverev in the semifinals of the BNP Paribas Open, but confessed after their latest tilt that he feels like the swing has been "two completely different tournaments."

"Coming here and trying to produce some good tennis was my main goal, and standing here again in the final means very much to me," he said in his on-court interview. "We'll try to push now in a couple of days, but in any case, it has been an incredible swing ... couldn't be better, and I'm very happy."

Sinner hadn't lost more than four games in a set against Zverev since last October's final in Vienna, until the German found his best tennis to stay ahead for much of the second set. In the inverse of the first, where Sinner saved a break point at 1-1 and stayed ahead from there, Zverev held serve in each of his service games in the second—including from 15-40 down at 4-4.

But Sinner's effectiveness on his own delivery allowed him to keep pace. He hammered 15 aces in the match, and lost just 10 points in six service games overall. He pulled away for the win by taking five of the last six points of the tiebreaker.

"Today has been a tough encounter," Sinner said. "He played some incredible tennis, so I was serving very well in the end, especially in the crucial moments. I am very happy and it means a lot to me."

Sinner will face Czech Jiri Lehecka in Sunday's final, with Lehecka bidding not just for his first title above ATP 250 level, but to beat Sinner for the first time. Lehecka hasn't won a set in their four previous matches.