It was a tough draw for the multi-Slam champions not named Nadal or Federer. (AP)

Roger Federer and Rafael Nadal may have been dominating men's tennis for the past year and a half, but the game's other superstars have all been working their way back into form. Chances are at least one of them is ready to take back the spotlight this fortnight—the only problem is they've all drawn difficult opening opponents.

Andy Murray versus Benoit Paire was the biggest opening men's match to watch, but Murray withdrew from the Slam on Sunday. 

Here are three first-round men's matches to watch out for:

1

1

Stan Wawrinka vs. Grigor Dimitrov

In 2017, this match would have made more sense as a Slam semifinal. But this year, the Swiss has struggled to string wins together in his comeback from knee surgery, and Dimitrov, winner of the 2017 ATP Finals, is now only 10th in the Race to London. With the field relatively open, both players will badly want to make a breakthrough at the All England Club. 

 

Press with a view! @fevertreechampionships @gettyimages @patriklundinphoto

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2

Novak Djokovic vs. Tennys Sandgren

After a difficult start to the season, Djokovic has been putting reasonably good results together on the clay and grass, culminating in his run to the final at the Queen's Club. Sandgren's season has taken the opposite trajectory, with a quarterfinal at the Australian Open and not much success since making the clay final in Houston. 

Still, this has been a breakout 2018 for the 26-year-old, and Djokovic will need to show up ready if he wants Wimbledon to be his first title of the year.  

 

Back to @wimbledon business ????????

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3

Gael Monfils vs. Richard Gasquet 

The two Frenchman are pals and former Davis Cup teammates, but it will be all business on Monday when they face off in the very first round. Gasquet is doing a little better these days, and his ranking shows it—he's ranked No. 31 while Monfils is No. 44. They last played each other in Eastbourne last year, on grass, with Monfils winning in three sets (two of the sets were tiebreaks).

Gasquet has the momentum thanks to his title win in s'-Hertogenbosch but Monfils leads their career head-to-head record 9-7.