The 2014 US Open champion, Marin Cilic, overcame rust and injury issues to defeat American wildcard Tennys Sandgren: 6-4, 6-3, 3-6, 6-3. The Croat will face Florian Mayer next.

After compiling a terrible – at least for a player of his status – 5-7 record in the first three months of the season, Marin Cilic has been one of the most shining stars both on grass and clay. That form brought him his second ever clay court title and his first Roland Garros quarterfinal. Then the Croat reached his second Grand Slam final, and his first at Wimbledon, losing in straight sets to Roger Federer. The injury that stopped him from playing his best against the Swiss also forced him to skip Montreal and Cincinnati. Thus the match against Sandgren was Cilic’s first in 43 days.

The 26-year-old American mainly competes on the Challenger Tour. However, due to a string of good results, his ranking became good enough to earn him a chance to play in a few ATP World Tour main draws this year. Sandgren’s best result was the third round at the Citi Open, where he defeated an ailing Nick Kyrgios by retirement and then played a decent match against the eventual winner of the tournament, Alexander Zverev.

The debutant surprised the crowd in the opening point, hitting a beautiful backhand winner down the line. Sandgren kept firm in the rallies and held his first service game, saving a break point with a stunning pass on the run. The difference started showing when Cilic led 2-1, as the Croat dominated baseline exchanges with very clean groundstrokes and broke to go up 3-1.

The former US Open champion was outplaying his opponent, hitting very clean groundstrokes and despite some occasional great shots from Sandgren, it was clear who the better player was. Cilic was close to go up 5-1, but the 26-year-old American saved two break points to keep Cilic’s lead to just one break. Shortly thereafter, the fifth seed had a brief moment of relaxation when he served for the set, giving his opponent a break point chance and out of nowhere, they were back on serve. However, he reacted instantly and re-broke to win the first set 6-4. Cilic won each of his 15 first serve points in the set.

Nonetheless, Cilic had started spraying errors left and right and got broken to start the second set. Sandgren knew that he had to capitalize on the unexpected break, but didn’t rise to the occasion, playing horribly to allow the Croat to level. The strange series of four breaks finally came to an end when the fifth seed held. He broke and held again in the blink of an eye to go up 4-1. That advantage turned out crucial. Cilic took the second set: 6-3.

Cilic’s first serve percentage was pretty bad the whole match and it failed him again in the second game of the third set. Down a break point, he put a routine forehand into the net. The Croat’s mixed powerful groundstrokes with terrible errors; particularly one of his forehand volleys, which likely will go down as one of the worst shots of the tournament. Cilic’s slump was still on as Sandgren had a break point for a 4-0 lead. The American had to save two break points serving for the set, but another mistake from Cilic allowed him to take it: 6-3. The Croat made 23 unforced errors in the third set alone.

Soon it became clear that Cilic’s struggles weren’t just down to lack of playing the last month as he didn’t even bother to chase down Sandgren’s drop shot in the opening game of the fourth set. Trouble soon followed for the Croat as he had to save a break point at 1-1, but he managed to hold. Cilic’s big chance would come in the eighth game. The American saved three break points but finally succumbed after a game that lasted ten minutes. The fifth seed took his chance holding to love in order to finish the match 6-4, 6-3, 3-6, 6-3.

It definitely wasn’t Cilic’s sharpest performance; the third set was downright terrible. Also, there is still a big question mark regarding the injury he has been carrying. His movement seemed a little worse than usual, especially in the third set but he still found a way to eventually clinch the match. The error count was nonetheless horrific – 57 errors in total, with of them being 27 forehand groundstroke errors. Another issue was Cilic’s first serve percentage as it found its place just 53% of the time. Maybe it was just rust. After all, a healthy former US Open champ is dangerous to anyone in the draw. We will have to wait until Cilic faces a more accomplished opponent to get a better understanding of his lingering issues.

Next up awaits Florian Mayer, who managed to defeat Rogerio Dutra Silva 7-5, 0-6, 6-3, 6-4. The German is a tricky opponent: he has defeated the Croat twice in the past, but if Cilic is healthy then it could potentially turn out like their Wimbledon encounter this year, where the eventual runner-up cruised to a straight sets victory. Hopefully, that match will give us more answers about the fifth seed’s state of health and form.

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