HALLE WESTFALEN (Germany) • Roger Federer, employing all the verbal dexterity he brings to any discussion on tennis, on Thursday lent his voice to the suggestion that Andy Murray's reign at No. 1 in the world is under serious threat for the rest of the summer.
"Andy was tired after getting to No. 1 at the end of last year and then has been struggling with injuries," the 35-year-old Swiss said in Halle before his 7-6 (7-4), 6-4 win over Mischa Zverev, the German left-hander who dumped Murray out of the Australian Open in the fourth round.
Federer, who is returning after taking 11 weeks off the Tour to prepare for his pursuit of an eighth title at Wimbledon, added: "I think the second part of the season will be really crucial for Andy, and Novak (Djokovic) as well. I think the second half of the season is going to be really, really interesting."
The victory puts Federer, who skipped the entire clay-court season, into the quarter-finals of a tournament he has won eight times and will next face the world No. 134 Florian Mayer.
More pertinently, the win lifts him back to No. 4 in the world, which keeps him away from Murray at Wimbledon until at least the semi-finals.
Federer, Rafael Nadal, Djokovic and Murray have allowed only occasional challenges to their hegemony for more than a decade.
Now there is insurrection in the air before Wimbledon: fans have deserted Murray, the defending champion, to back Federer into 5-2 favouritism, according to Ladbrokes. If he wins a ninth title in Halle, he will move up to third seed at Wimbledon.
At Queen's Club in London this week, the vulnerability of Murray and Stan Wawrinka - who refuses comparison with the supposed big four despite reaching his fourth Grand Slam final at the French Open this month - was painful for them and their supporters.
Murray, the five-time champion, lost to Jordan Thompson, a young Australian hustler ranked 90th in the world, while Wawrinka went out in two sets to Feliciano Lopez.
Murray's first-round exit extended a miserable first half of the season, which has seen the Scot win just one tournament and lose nine singles matches already.
But neither Murray nor Wawrinka was as poor as Djokovic at Roland Garros.
Djokovic, who plays at Eastbourne next week, a rare warm-up on grass before Wimbledon, is probably in deeper trouble after his meltdown in Paris against Dominic Thiem.
Nadal, who beat Wawrinka there for his 10th title, withdrew from this tournament to safeguard his knees.
Uncertainty has gripped the game again, which will lend Wimbledon an added edge when the first ball is struck on July 3.
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