INDIAN WELLS, CA, USA -- Elena Vesnina kicked off her BNP Paribas title defense with a thrilling come-from-behind victory over 18-year-old American Catherine “CiCi” Bellis, winning 12 of the last 14 games to triumph 2-6, 6-1, 6-1 on Saturday at Indian Wells.

The 24th-seeded Russian started very slowly and her reign as champion looked as though it would come to an abrupt end, but upped her game significantly in the final two sets to clinch the win in 94 minutes.

"I'm really happy that I won this first-round match," Vesnina told the press, after the match. "It's never easy to play first match in any tournament, and in this tournament especially for me."

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"CiCi, she's having a great season," Vesnina continued. "She's only 18 years old. You know, when they announced that and they said highest ranking is 35 in the world, I was like, 'Whoa, that's impressive.'"

"She has a bright future. She's a really talented girl, good fighter. Yeah, I'm just happy that I won this match."

Vesnina’s path to hoisting the trophy again gets no easier in the third round, as the Russian will face either former World No.1 Angelique Kerber or her long-time doubles partner, compatriot, and fellow Olympic champion Ekaterina Makarova in the second round.

At the outset, the young American exhibited the skills which has already pushed her into the Top 40 of the WTA rankings, and made her a dangerous opening opponent for the title holder. After the combatants exchanged breaks to get to 2-2, the teenager broke Vesnina at love to lead 3-2, after hitting a scorching return winner on break point.

Vesnina struggled with her serve in the opening frame, winning only 29 percent of points on her first delivery. Bellis took advantage, breaking Vesnina once more to lead 5-2, and then calmly closing out the set in the next game when the Russian pushed a backhand service return into the net down set point.

"I was trying to be too close to the lines, you know," Vesnina explained. "In the end of the first set, I called my dad and he told me, 'Just give your some space before the line. You have the whole court. Don't try to be too clean.' And that actually worked."

The turnaround was swift and decisive for the defending champion in the second set. Suddenly, the excellent Vesnina serve, which has carried her to three Grand Slam doubles titles and an Olympic gold medal in doubles, made an appearance.

The Russian broke Bellis for a 2-0 lead, and then broke again for 4-0, after the American hit two consecutive double faults. A backhand winner on game point at 5-0 finally put Bellis back on the board, but Vesnina, who won 92 percent of points on her first serve in the set, was unstoppable at the line at that point, and she tied up the match at one set apiece.

"When I won those two games in the second set, I felt more confident after that and I started to play more free," said Vesnina. "Because in the first set, I was kind of tight and not really precise with my shots. Then the second set and the third set it started working well, and my serve, as well."

There was a potential momentum shift in the third set, as Bellis fended off two break points in the first game, to hold for 1-0. Vesnina then squandered double break point at 1-1, and Bellis reached game point thrice in that game.

Had the American converted one of those game points and held for 2-1, denying Vesnina any service breaks after four chances in the first two games of the set, the match could have ended differently. But Vesnina reached a third break point via strong returns, and then grabbed the break by forcing an error from Bellis with a crushing overhead.

The wind went out of the Bellis sails at that point, and the deflated teen's unforced errors mounted while Vesnina's aggressive game reached its peak potential. Bellis had a break point at 4-1 for her last gasp, but Vesnina held for 5-1 behind two aces in the next three points. One final break for the Russian led her to a strong comeback victory via six consecutive games, opening her title defense with a bang.

"This tournament was always, for me, like one of the favorites," said Vesnina. "I was always happy to come back here, and I was always enjoying my time here. It's just, like, you know, just clicked. Everything worked in the right way for me last year."