LONDON (AP) As usual, Roger Federer, Novak Djokovic, Rafael Nadal and Andy Murray are playing well at Wimbledon, leading the way into Week 2.
''It's their turf,'' said Ernests Gulbis, who stood in Djokovic's way in the third round but failed to present too much of an obstacle. ''It's their home court.''
Indeed, it is.
Not since Lleyton Hewitt won the championship 15 years ago has someone other than Federer (a record-equaling seven titles in that span), Djokovic (three), Nadal (two) or Murray (two) left Wimbledon with the men's singles title. In addition, that so-called Big 4 accounts for eight runner-up finishes during that stretch.
Count Federer among those shrugging at the quartet's success so far this fortnight, with only one set dropped among the lot.
''I thought that everybody this week was going to find their form, especially speaking about Andy and Novak. ... With me, I hoped I was going to be there. Whereas with Rafa's confidence, I thought he was also going to be there,'' said Federer, who has a cold. ''So I'm not that surprised. But it's great.''
This Grand Slam season has been just like old times.
Following a period in which Djokovic, then current No. 1 Murray overtook Federer and Nadal in the rankings, and started regularly appearing in - and winning - major finals, the latter two have reasserted themselves.
First, Federer returned from missing the last half of 2016 while letting his surgically repaired left knee heal and has been as impressive as he's been in quite some time. He won his first Grand Slam title in 4+ years at the Australian Open, beating long-time rival Nadal in the final.
If that was the first indication that Nadal, too, was truly back after his own health issues, another one came at the French Open, where he won his record 10th trophy in fantastic fashion, not dropping a set. He's now run his consecutive sets streak at majors to 28, tying his personal best and, in the Open era, sitting behind only Federer's run of 36 from 2006-07, and John McEnroe's of 35 in 1984.
''Against Rafa,'' said the man he defeated in the third round, 30th-seeded Karen Khachanov, ''if you give him time, he can destroy you.''
As Federer alluded to, it's been Djokovic and Murray who arrived at the All England Club having been less than their best this season.
But with Andre Agassi and Mario Ancic in his coaching corner, Djokovic seems rejuvenated. Defending champion Murray is the only member of the foursome who hasn't won every set he's played in the tournament: Against Fabio Fognini in the third round, he ceded one and saved five set points to barely avoid losing another.
The men's fourth-round matchups on the top half of the draw Monday are Murray vs. Benoit Paire, Nadal vs. No. 16 Gilles Muller, No. 7 Marin Cilic vs. No. 18 Roberto Bautista Agut, and No. 24 Sam Querrey vs. Kevin Anderson. On the bottom half, it's Djokovic vs. Adrian Mannarino, Federer vs. No. 13 Grigor Dimitrov, 2016 runner-up Milos Raonic vs. No. 10 Alexander Zverev; and 2010 runner-up Tomas Berdych vs. No. 8 Dominic Thiem.
Wimbledon is the lone Grand Slam tournament that schedules all 16 remaining singles matches on the same day.
The top-half women's fourth-rounders: No. 1 Angelique Kerber vs. No. 14 Garbine Muguruza in a meeting of the past two runners-up, two-time major champion Svetlana Kuznetsova vs. 2012 runner-up Agnieszka Radwanska, No. 5 Caroline Wozniacki vs. No. 24 CoCo Vandeweghe, and Magdalena Rybarikova vs. Petra Martic. In the bottom half, it's five-time champion Venus Williams vs. No. 27 Ana Konjuh, No. 2 Simona Halep vs. two-time Australian Open champion Victoria Azarenka, French Open champion Jelena Ostapenko vs. No. 4 Elina Svitolina, and No. 6 Johanna Konta vs. No. 21 Caroline Garcia.
At 37, Williams is the oldest woman left. At 19, Konjuh is the youngest.
There is an interesting age dynamic in the men's event, too: The seven players 30 or older in the round of 16 represent the most to get that far in the 50 Wimbledons of the Open era.
Federer turns 36 in a month, Nadal is 31, and Djokovic and Murray are both 30. They're joined by Muller (34), Anderson (31) and Berdych (31).
''I came through the juniors with all these guys. It's nice to see them still hanging on, still enjoying the tour, still being tough out there, making it difficult for the youngsters to break through,'' Federer said. ''There is a bit of that clash right now - the young ones trying to push out, especially, the 35-plus guys. But then there's a strong, strong team, as well, around the generation of Rafa and Murray and Djokovic, obviously.''
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