LINZ, Austria - No.2 seed Elise Mertens shook off a slow start to dispatch an inspired Anhelina Kalinina, 2-6, 6-1, 6-2 to reach the second round of the Upper Austria Ladies Linz.

"It may not have been the best match I played," she said after the match. "It was a bit of a struggle in the first set. She played pretty aggressively and didn't make a lot of mistakes. I tried to change in the second and third sets where I was stepping into the court more. I was mentally prepared for a battle, and it was certainly a battle until the end."

The former Australian Open semifinalist concluded first round action in Austria with an entertaining comeback victory, wrapping up the win over the qualifier after two hours and five minutes on Centre Court. 

A former junior standout who finished runner-up to Marie Bouzkova at the 2014 US Open girl's event, Kalinina came close to a Top 100 debut and major breakthrough four years later in Flushing Meadows when she nearly dethroned defending champion Sloane Stephens. The American ultimately advanced in three sets, and Kalinina since endured a backslide in the WTA rankings from her career-high of No.107.

Against Mertens, who is fresh off a second straight US Open quarterfinal and J&T Banka Ostrava Open doubles title with Aryna Sabalenka, none of that was apparent as the 23-year-old was first to break and fought through successive marathon games late in the first set to take it after 43 minutes.

"I felt everywhere and nowhere in the first set. I was reaching a lot and not getting a lot of depth on my shots. I was too far behind the baseline to hit the angles I needed."

Undaunted, Mertens emerged on top after an exchange of breaks in the second set and was soon ahead 5-1, saving a late break point to level the match on her second opportunity.

"The whole has to be played, whether it's two sets or three. The opponent still has to win two sets, so I just started fresh after the first set. She may have had an advantage, but I was trying to find solutions, and do things I wasn't doing at first. I kept myself going, stayed positive, and that worked."

The deciding set began with each woman saving a break point, but it was the Belgian who broke first, moving ahead with the help of some decisive hitting from the baseline. Surviving a seven minute serve game that followed, she put away a powerful overhead to consolidate and broke once more as Kalinina netted a forehand.

"She was really attacking my second serve with her backhand, so I tried to put in more body serves to her forehand. From the backhand side, she was able to go down the line or cross-court from the ad side. I found I was reaching less for shots after the first set. Once I made my first serve, I knew I had the advantage."

Roaring ahead three match points, an ace put the No.2 seed over the finish line and into the second round.

Up next for Mertens is former World No.2 Vera Zvonareva, who outfoxed Ukrainian teenager Marta Kostyuk in straight sets on Tuesday. The two have faced off twice in the last few weeks in doubles, with Zvonareva partnering Laura Siegemund to defeat Mertens and Sabalenka en route to the US Open title only for the Belgian to avenge the defeat in Ostrava when the Russian paired with 2017 French Open champion Jelena Ostapenko.

"Doubles and singles are a bit different, so I'll have to look at how she plays. She's obviously a very experienced player with a lot of matches under her belt. I'm really excited for the match tomorrow."

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