Roger Federer avoided a major setback in his preparations for Wimbledon as he scrapped to a 7-6 (7/5), 4-6, 7-5 victory over Frenchman Jo-Wilfried Tsonga in the second round of the ATP event in Halle on Thursday.

Federer, 37, appeared firmly on course for a place in the quarter-finals at a set and a break up before an impressive comeback from Tsonga took the match to a decider.

The Swiss, who is eyeing a record tenth career title at Halle this year, prevailed in a tense third set and faces Spaniard Roberto Bautista Agut in the last eight on Friday.

Bautista Agut promised to take the fight to Federer after he eased to a 6-1, 6-4 victory over France’s Richard Gasquet.

Home favourite Alexander Zverev also advanced to the quarter-finals with a comfortable 6-3, 7-5 win over American Steve Johnson.

The world number five faces Belgium’s David Goffin in the last eight on Friday.

Also, Italy’s Matteo Berrettini, who was crowned champion in Stuttgart last week, came from behind to beat compatriot Andreas Seppi 4-6, 6-3, 6-2 and secure a quarter-final clash with third-seeded Russian Karen Khachanov.

Elsewhere, top seed Stefanos Tsitsipas came within three points of becoming another big-name casualty on Thursday at the Fever-Tree Championships, but fought back to reach the quarter-finals on his debut at The Queen’s Club.

The top-seeded Greek broke back when Jeremy Chardy served for the match at 5-4 en route to a 4-6, 7-6(0), 7-6(4) victory over two hours and 38 minutes.

Earlier in the day, the 20-year-old Tsitsipas had completed a 6-3, 7-5 first-round win over Kyle Edmund, carried over from Wednesday evening due to rain.

The world number six also saw his chances of winning a first title on grass helped as defending champion Marin Cilic and last year’s Wimbledon finalist Kevin Anderson crashed out in the second round.

They were followed by three-time Grand Slam champion Stan Wawrinka as 37-year-old French qualifier Nicolas Mahut came from a set down and a break down in the deciding set to win 3-6, 7-5, 7-6 (7/2) in their second-round clash.

Anderson battled back from a set down to Gilles Simon, but the Frenchman prevailed 6-1, 4-6, 6-4.

Fifth-seeded Cilic -- who also won the Queen’s title in 2012 and reached the final on two other occasions -- went down 6-4, 6-4 to 26-year-old Argentinian Diego Schwartzman.

Meanwhile, Juan Martin del Potro faces a further lengthy injury layoff and will miss Wimbledon next month after fracturing the patella in his right knee for the second time in nine months.

The Argentine slipped on court towards the end of his first round win at Queen’s Club in London over Denis Shapovalov on Wednesday and could also miss the US Open later this year.

Elsewhere at the Birmingham Classic on Thursday, world number one Naomi Osaka succumbed to a straight sets defeat to Yulia Putintseva, handing Ashleigh Barty the chance to end the week on top of the rankings. Osaka admitted ahead of her first grass court tournament of the season that she is still not at home on the surface and it showed as Putintseva romped to a 6-2, 6-3 win.

The US and Australian Open champion now runs the risk of heading into Wimbledon short of match practice on the grass as she has not signed up to play in Eastbourne next week.

French Open champion Barty eased into the quarter-finals with a 6-3 6-1 victory over Jennifer Brady.

At the Mallorca Open, Maria Sharapova’s return from injury came to an abrupt end on Thursday as she was convincingly beaten 6-2, 6-3 by Angelique Kerber.

Sharapova had not played since the end of January after taking time out to recover from a shoulder injury and her lack of sharpness was exposed by Kerber, who cruised into the quarter-finals.

Kerber will now face either Spaniard Paula Badosa Gibert or France’s Caroline Garcia, who play later on Thursday, for a spot in the last four.

Belinda Bencic is a potential semi-final opponent in Mallorca, after the Swiss came from a set down to beat America’s Shelby Rogers 5-7, 6-3 3-1.

Bencic will now play another American in the quarters, teenager Amanda Anisimova, who defeated France’s Alize Cornet 6-2, 6-4.

Agence France-Presse