Serena Williams has her eye on winning the final of Wimbledon. Photo: Han Yan/Xinhua

LONDON Patrick Mouratoglou has steered Serena Williams to some of her greatest achievements, but the coach has never seen the American work as hard as she has to battle back from injury and illness in pursuit of a record-equalling 24th Grand Slam singles title.

Williams will face unseeded late-bloomer Barbora Strycova on Thursday for a place in the Wimbledon final, having begun the tournament short on match practice and with question marks hanging over her prospects.

The 37-year-old had barely played since the Australian Open in January after a niggling knee injury limited her court time and the rust was all too visible as she began her campaign at the All England Club.

Yet, after suppressing tigerish American Alison Riske on Tuesday in the last eight, only Czech Strycova, the oldest first-time Grand Slam singles semi-finalist at 33, stands between Williams and another shot at Margaret Court's record 24 slams.

It is a number that has dominated Williams' late career, especially after she returned to the sport following the birth of her daughter in 2017 when she suffered a pulmonary embolism that left her bedridden for six weeks.

"Twenty-four will mean that she will equal the record of all time... and that's why she came back to playing tennis after having a baby and so many medical complications. The effort she has put in, I have never seen something like this," Mouratoglou told reporters on Wednesday.

"You have no idea how much she worked, how hard she worked to come back to that level and she came back for that (record) so it will probably mean a lot if she makes it."

Mouratoglou started coaching Williams in 2012 and has guided the American to her fifth, sixth and seventh Wimbledon titles, an Olympic gold medal, three further U.S. Opens titles and two more French and Australian Opens.

In the run-up to Wimbledon, however, injuries and illness had limited Williams to just seven matches since the Australian Open in January.

According to Mouratoglou, Williams has been playing without any pain for three weeks and is feeling "so much lighter" in spirit  an ominous warning to Strycova, who has played the American on three occasions and lost every time.

"She is in a good place at the moment, she is happy, has a house, her husband is here her daughter is here and she is pain free," he said.

"In the last match you could see that she has been able to raise her level when it was necessary, which is one of her trademarks and this is back so everything is positive." 

Reuters