As tennis turns to Wimbledon, there’s been a bit of a throwback feel to this Grand Slam season.

At the year’s first major tournament, the Australian Open in January, Roger Federer beat Rafael Nadal for the men’s title and Serena Williams defeated her sister, Venus, in the women’s final.

Matchups from a decade ago or more, right?

Then, at the French Open in May and June, Nadal reached a second straight major final for the first time since 2014, and won one for the first time since that year.

And now, when play begins Monday at the All England Club, so many of the key storylines will involve those same four players: Federer and Nadal because of their recent resurgence; Serena Williams because of her absence (she’s expecting a baby in September); Venus Williams because she’s one of only two past champions in the women’s draw.

Here’s what to watch on the grass courts of the year’s third Grand Slam tournament, which starts Monday:

FEDERER THE FAVORITE

Wasn’t all that long ago that folks were figuring Federer’s best days were long behind him. He hadn’t won a Grand Slam title since 2012, and as he entered his mid-30s, he was missing Grand Slam tournaments for the first time in more than 15 years because of injury. And now? He extended his record with an 18th major championship in Australia, opened the year 19-1, took some time off and then won a grass title at Halle, Germany. With defending champion Andy Murray off form this season, Federer is a popular pick to win Wimbledon for what would be a record eighth time.

NADAL GOES FROM CLAY TO GRASS

There was a time that Nadal excelled on any surface, winning Wimbledon twice and reaching the final on three other occasions while marching toward 10 French Open titles and completing a career Grand Slam, too. But then his knees became a real problem on grass and he not only started losing early at the All England Club, he started losing to players ranked 100th or worse. “When Rafael is good with his knees,” said Nadal’s uncle and coach, Toni, “he can play well on the grass.”

WHO’S MISSING

Not only is seven-time Wimbledon champion Serena Williams absent, but so is 2004 champ Maria Sharapova, who was forced to sit out last year’s tournament during a 15-month doping ban. She would have needed to qualify this time but is now sidelined by a left thigh injury. Their absences lend the same sort of wide-open feel to the women’s draw that the French Open had.

VENUS, KVITOVA, AZARENKA

The two past winners in the women’s field are Venus Williams, a five-time champion, and Petra Kvitova, a two-time champ. Both will get plenty of attention, for very different, non-tennis reasons. Williams was sued Friday by the estate of a Florida man who died after a car crash police say she caused. Kvitova was attacked by a knife-wielding intruder at her home in the Czech Republic in December. Kvitova wound up with cuts to her left hand – the one she uses to swing a racket – and needed surgery.