Jessica Pegula's third-round loss leaves the No. 3 seed frustrated, and ensures a surprise semifinalist

WATCH: Mertens finished off Pegula on Friday morning

After Jessica Pegula lost 10 consecutive games to Irina-Camelia Begu in a match earlier this year in Charleston—and then proceeded to win the next and final six games—she was asked how such a sudden and massive turnaround occurred.

“I’m tough,” she told on-court interviewer Andrew Krasny.

After Pegula lost seven of the first eight games in her match Friday at Roland Garros against Elise Mertens, to fall behind a set and a break, the No. 3 seed showed some of that trademark toughness. She broke the Belgian right away and then, while returning up 3-2, earned a chance to take a second-set lead.

The American squandered that break point in a six-shot rally, and then fell behind 3-4. That’s when a five-deuce, 16-point game ensued, during which Pegula earned three more break opportunities.

Pegula played tough when the chips were down. Problem was, Mertens played even tougher.

“When you have that type of game, it’s a huge momentum shift,” said Tennis Channel analyst Chanda Rubin at Roland Garros. “It can go one way or the other.

“Pegula really needed that game to get herself into the match, give herself a chance in that second set…that one was pivotal.”

Unable to break Mertens, the air left Pegula’s sails, and she lost the third-round match, 6-1, 6-3. Over an hour and 22 minutes, Mertens struck 20 winners against 13 unforced errors, while Pegula racked up 28 UEs—a sky-high total over just 16 games—against 19 winners.

“I think the third round is always tough because you very often meet a seeded player, and that was the World No. 3, so that was going to be a tough one,” said Mertens. “I think I was mentally prepared to fight.”

Pegula’s clay-court season, at least in singles, comes to an end with an 8-4 mark on dirt, but with no titles or runner-up finishes.

The latest loss is surely a frustrating one for the 29-year-old, who was defending quarterfinal points in Paris and had reached the elite eight at four of the last five majors. It will take her out of the tour’s Top 3, a group she is of course included in from a rankings standpoint, but often informally excluded in favor of Elena Rybakina, the champion in Rome, Indian Wells and Wimbledon. (Rybakina, who has established herself in matches against world No. 1 Iga Swiatek and No. 2 Aryna Sabalenka, did not receive ranking points for winning Wimbledon last year, but that is beside the point.)

As Roland Garros goes, the Buffalo, N.Y. native’s exit makes her quarter of the draw, already considered to be the weakest of the four, even more wide open. Begu, as it turns out, is the highest-seed player that could reach the semifinals at No. 27, with Mertens just behind. No other seeds remain.

Pegula’s time in Paris isn’t over—she’s still competing in doubles, with Coco Gauff. But despite their No. 2 seeding, the Americans will face a stiff second-round test in Victoria Azarenka and Beatriz Haddad Maia. All four of the competitors are in the Top 18 in singles, with the Brazilian also ranked No. 12 in doubles.

As she did in the finale of spring hard-court season, in Miami, Pegula hopes to end this stretch of surface play with a doubles title. But she’d surely like to have ended Miami and Roland Garros—and, down the road, Wimbledon and the US Open—raising a trophy by herself. Smaller titles would do, too. For all she’s accomplished in the world rankings, Pegula owns just two singles titles, and has only won one since 2000 (last fall, at the WTA 1000 in Guadalajara).

Pegula’s propensity to play singles and doubles—along with mixed, at the majors—will likely be questioned after this early exit. But it’s not as if she was worn down in the second week by an extended run in doubles or mixed—though she has played five total matches over the tournament’s first six days. She was also recovering from a recent bout of food poisoning.

“I was throwing up for the whole night and I couldn’t sleep much,” Pegula told the BBC this week, about her arrival in Paris last week. “I didn't practice [last] Wednesday, I practiced on Thursday—but it was not pretty. I could barely do anything.”

Asked about her scheduling after her second-round singles win, Pegula told Tennis Channel’s Prakash Amritraj that “I just like to play. I like to compete, I like to stay feeling in that mindset.

“Maybe I’m just trying to make my odds a little bit higher to win more matches,” she added with a laugh. “To me it’s just fun...Everyone always asks me why, but I’m like, why not?”

With another summer of high seedings on the horizon, at tournaments on faster surfaces and closer to home, Pegula will have plenty of opportunities to play, and to win. It will be up to her to turn quantity into quality, or more questions will come.