Petra Kvitova declared herself a serious contender for the 2013 Wimbledon title over the course of two days and what might be called a typical Kvitovian roller-coaster ride, featuring repeated climbs to the heights of competence and ecstasy followed by plunges into the depths of bumbling and despair.

You think I’m just mindlessly churning out purple prose here? Get this: from 3-all in the first set (yesterday) of this third-round clash with Ekatarina Makarova, Kvitova won six straight games. Then Makarova won the next eight. As rain sprinkled down and light faded at Wimbledon, Kvitova held a long service game to end the day on about the most threadbare up-note you can imagine. She was still down a break at 1-2 in the third set when the women quit the court.

If you detect a theme here, you’re right. Today, in the bright sunshine and dry conditions that so help the big, left-handed, former champion’s game, Kvitova immediately broke Makarova to level at 2-all, and held to nose ahead. We were well into the sixth game when Makarova finally won her third point of the day. She forged ahead 40-15 in that game, but Kvitova began blasting those “Where did THAT come from?”-winners again, and three forehand placements later she had the break with serve to come, 4-2.

That forehand of Kvitova’s deserves further study, because it’s so ghastly at times for the same reason it’s so dazzling at others. It’s an extremely unstable-looking stroke, almost a caricature of whatever it is that makes so many lefty forehands turn out so, well, radical. Look at Rafael Nadal’s punched forehand, or that shoveling shot of John McEnroe’s, both of which worked pretty well in a pinch.

Anyway, that forehand is the tennis equivalent of a volatile explosive, and you know it’s going to blow up at any moment—although you’re never sure in which player’s face.

Serving up 4-2, we saw Kvitova’s entire career encapsulated in one game. She hit a horrific forehand to start it off, then managed to hook it true through a long rally ended by a Makarova winner. Kvitova then cracked a wonderful inside-out forehand winner off Makarova’s service return, French braid and left foot flying behind her. Then, a double fault: 15-40. At break point, Kvitova ended a brief rally by punching a wild forehand well wide of the line.

Back on serve. I probably wasn’t the only one who was suddenly haunted by memories of Isner vs. Mahut.

But to her credit, Kvitova sloughed off her loss of form. Serving down 3-4, Makarova jumped to a 30-love lead. But then Kvitova’s game clicked again as she smacked winnners to win the first three points. Makarova staved off the first break point with a service winner, after which Kvitova drilled the worst serve of the match—a floating second serve that barely made it into the box—out of court. But Kvitova exonerated herself with a confident attack and smash to secure the break, 5-3. She then served it out with uncharacteristically little drama to win, 6-3, 2-6, 6-3.

!IBM Stat of the Match:Makarova won five more points—93 to 88—but still lost the match, which tells you how effectively Kvitova can hold serve.

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