Serena Williams in action at the USTA Billie Jean King National Tennis Center in Flushing, NY.

Serena Williams has kicked off at the US Open her quest for the first calendar grand slam in 27 years, with a quick despatch of her Russian opponent, Vitalia Diatchenko, 6-0, 2-0.

The 86th ranked Diatchenko was unable to continue after 30 minutes against the player she calls her idol and retired with what appeared to be a foot injury.

The Russian had taken a bathroom break after the first set and called for the WTA trainer a second time at what turned out to be the end of the match.

Diatchenko won a total of five points, compared to 32 for the six-time US Open champion.

“I told her I was proud of her for coming out here, even though she was already injured,” #Serena said in her on-court interview. “That’s was a great effort. Hopefully we’ll be able to play again soon.”

Rafael Nadal, an old champion, who has had issues with his game this season also prevailed in his first match against rising Croat star, the teenage Croat Borna Coric. In their only other encounter, on the hard courts of Basel last year, Coric beat Nadal in the quarterfinals.

On Monday evening, a more confident #Nadal outmatched his younger opponent 6-3, 6-2, 4-6, 6-4.

“I played a very high level in the first two sets,” Nadal told ESPN’s Darren Cahill on court after the win. “I get tired a little bit in the third set; in these conditions I [suffered], but in the fourth I served well and was able to play aggressive again.”

In a tight first set, at 3-4, Nadal hit a sharply dipping backhand at Coric’s feet and followed it with a whipped forehand pass. After Coric duffed an easy overhead, Nadal capitalized on the first of three break points with a delicate, looping forehand pass over Coric’s outstretched racquet. Nadal closed out the 33-minute set at love with a trademark pummeled forehand winner down the line.

Nadal rolled to an easy two-set advantage, but Coric finally broke at 4-5 in the third to snatch the set, as Nadal’s winning percentage on second serves dipped to a paltry 27%. With Coric growing in confidence in the fourth set, intent on taking the match the distance, Nadal suddenly struck with a wicked forehand winner to break serve and seize the lead, 4-3. The question that has bedeviled the Spaniard all year – can he close the match? – was definitively answered at 5-4 as Nadal, dripping with perspiration, reached 40-0 on his serve, punctuating match point with a roundhouse fist pump and a cry of “Vamos!”

The Spaniard closed it out with a big serve down the middle, angling away from Coric. For the match, Nadal won an impressive 88% of his first-serve points (but only 36% of second serves) and capitalized on 16 of 17 net approaches.