NEW YORK, NY, USA - No.24 seed Garbiñe Muguruza suffered her second consecutive opening round loss at a major on Tuesday, and leaves the US Open with more questions than answers regarding her game, her coaching situation and her upcoming Asian Swing schedule. 

The two-time Grand Slam champion made a solid start on Grandstand against Alison Riske, an unseeded American with two WTA titles under her belt. But Riske, who has built up a reputation this summer for her never-say-die comebacks, pulled off another stunner to knock out Muguruza, 2-6, 6-1, 6-3. 

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In her post-match press conference, Muguruza chalked up the outcome to a surge in level from an in-form opponent. 

“In the first set I did play well,” Muguruza acknowledged. “She did few mistakes that I, you know, got the opportunity and I went for. It was very competitive. Every game we had breakpoints and then we were breaking a lot each serves. 

“She found very good shots [in the] second and third set, a lot of lines. We always have tough matches, and I think she's playing great now.”

It’s a disappointing setback for Muguruza, who is seeking to build up a consistent momentum and get back to her world-beating ways: the Spaniard has suffered a slow slide down the rankings as she’s struggled to string together consistent wins. A title defense at Monterrey in April remains Muguruza’s only final in the past 12 months, and she came into the US Open with opening defeats at Wimbledon and Cincinnati. 

“After a match like this, we need to evaluate things coldly,” Muguruza told Spanish journalists. “You’ve got to step back and give it a bit of distance, right now we’re all emotional, and after the first round of a Grand Slam it always hurts, logically.”

In her search for a change, Muguruza parted ways with coach Sam Sumyk after Wimbledon, ending a four-year partnership that saw her claim two Grand Slams and reach the WTA World No.1 ranking.

Muguruza worked with Medina Garrigues (left) in Cincinatti and New York. (Jimmie48 Photography/WTA)

Retired Spanish player and Fed Cup captain Anabel Medina Garrigues has since taken up the coaching reins in Cincinnati and Flushing Meadows, but Muguruza told press that she’s not in a rush to fill Sumyk’s old position during the final stretches of the season.

“At the moment I don’t have anything set in stone, I’m going at it week by week,” Muguruza elaborated during the Spanish portion of her press. “I don’t feel any particular rush to hire someone as a coach, but it is important to choose well. 

“Right now I’m going through this interesting period with Anabel here. We’ll see who will come with me to Asia. It’s exciting to see how this is all going to go.”

Muguruza had nothing but praise for the retired Spanish player, who claimed two Grand Slams in doubles at Roland Garros, and in 2017 coached Jelena Ostapenko to victory at the same tournament.

“I’m happy to have Anabel on my bench. At the end of the day, she’s the Spanish Fed Cup captain, I’ve played with her during her playing days. She’s like just another teammate. She knows me very well.”

Departing the US Open in the first round for the first time since 2014, Muguruza is looking ahead to the Asian Swing, where last year she reached a pair of semifinals in Hong Kong and the WTA Elite Trophy in Zhuhai.

In the meantime, Muguruza will be keeping her eyes peeled for new opportunities, and has already formed a list of the qualities she’s looking for in her ideal coach. 

“A good coach for me would be someone who knows tennis at the highest level,” she reflected. “They should have a strong character. And they should be someone that gets along with people. 

“For me, those are the three most important keys.”