Jannik Sinner will face Hubert Hurkacz in his first ATP Tour-level grass final after overcoming Zhang Zhizhen 6-4 7-6 (7-3) in the last four at the Halle Open.

The world number one entered Saturday's clash with Zhang, ranked 42nd in the world, on a 35-match winning streak against players outside the ATP's top 20.

There was to be no upset in North Rhine-Westphalia, though Zhang pushed him close in a match that featured just one break – Sinner doing the honours in the ninth game of the opening set.

Zhang failed to convert the lone break point generated in the second set as both players served confidently, the Chinese number one winning 79% of first-serve points to Sinner's 75%.

However, the Italian's quality shone through in the tie-break, the Australian Open champion converting his third match point to advance. 

Hurkacz will be his final opponent after he pulled off an upset of Zverev earlier on Saturday, the fifth-seeded Pole producing a big-serving display in a 7-6 (7-2) 6-2 win.

Sinner and Hurkacz played doubles together earlier this week, saving two match points in a thrilling win over Nathaniel Lammons and Jackson Withrow before going out to French duo Sadio Doumbia and Fabien Reboul the following day.

Data Debrief: Sinner matches Federer and Medvedev

Sinner will have a chance to capture his first title on grass on Sunday, which would represent the best possible preparation for a tilt at Wimbledon.

He is just the third player to reach the Halle Open final while top of the world rankings, after Roger Federer (in 2004, 2005, 2006, 2008 and 2018) and Daniil Medvedev (2022).

Daniil Medvedev crashed out of the Halle Open in the second round on Wednesday, succumbing to a 6-3 2-6 7-6 (7-5) defeat to Chinese number one Zhang Zhizhen.

Medvedev looked to be on course for the third round at 5-3 up in the decisive tie-break, but Zhang won four successive points to reach the last eight.

Zhang had earlier dropped six straight games from 2-2 in the second set, but he responded to losing an early break in the decider with one of his own to restore parity, then came on strong in the tie-break.

He will face Christopher Eubanks in the next round after the American eliminated defending champion Alexander Bublik with a 7-6 (7-5) 4-6 6-3 victory.

Meanwhile, second seed Alexander Zverev avoided an upset as he saw off a spirited performance from Lorenzo Sonego, winning 6-4 7-6 (7-5) to tee up a meeting with Arthur Fils.

Data Debrief: Zhang breaks new ground

Zhang's victory saw him become the first Chinese player to reach the Halle Open quarter-finals, also representing his second top-five victory after he beat Casper Ruud at last year's US Open.