BIRMINGHAM, Great Britain -- Petra Kvitova's stellar 2018 season continued in Birmingham on Sunday, as the No.4-seeded Czech overcame Slovakia's Magdalena Rybarikova, 4-6, 6-1, 6-2, to defend her title at the Nature Valley Classic.

"I didn't really expect to win here," Kvitova exclaimed, during her post-match press conference. "I just played match by match, being very happy to be on the grass and the tennis court....For me, I'm surprised."

The former World No.2 picked up her WTA-leading fifth title of the year, as well as her 37th match victory this season, which also leads the tour. Kvitova improves to 2-0 against Rybarikova on the WTA, having also defeated the Slovak in the final of the Connecticut Open in 2014.

"I'm already pleased with this part of the season," Kvitova continued. "I couldn't imagine to have five titles this time of the year, so I'm pretty happy already."

Kvitova said that Rybarikova is "a tricky player, so it's always time to get used to. She has a little bit different serve as well. We practiced one day here one day before the tournament, but still a match is a match. I needed a little bit of time to get used to spins and slices and volleys and whatever she plays just starting a game."

Both players had a nearly equal amount of unforced errors, but Kvitova hit 34 winners during the two-hour and five-minute encounter, in contrast to Rybarikova's 18. Kvitova also won 70 percent of points on Rybarikova's second serve.

"I think today was a great final to kind of fight," Kvitova continued. "We played over two hours, so it was a great final to watch I think, I hope."

The combatants both started the match by getting through their opening service games with fiery serving, mixing well-placed, powerful deliveries with double faults. But Kvitova quickly blinked on serve at 1-1, blasting a forehand error to give Rybarikova triple break point, and firing another miscue from that wing to drop serve at love.

Rybarikova could not hold onto the lead for long, as Kvitova broke for 3-3 on her fifth break point of that game by forcing an error with a strong backhand. But the Slovak dominated Kvitova in another of the Czech's service games, using deep returns to once again break Kvitova at love and lead at 4-3.

Serving for the set at 5-4, the Slovak fended off a break point before closing out the opener after Kvitova punched a backhand volley attempt into the net. Both players had 10 winners in the first set, but Kvitova had a whopping 22 unforced errors, to Rybarikova’s 15.

"I really fought back to get the break back," said Kvitova. "Then she hit unbelievable to break me again. And it was tough to win the first set. I had chances, but she was little bit better in that."

However, vintage Kvitova appeared in the second set. The two-time Wimbledon champion used searing service returns to break Rybarikova at love for a 2-0 lead, and then staved off a break point in the next game with a forehand winner, eventually holding serve for 3-0.

At 4-1, a grueling all-court rally was polished off with a forehand winner by Kvitova, giving the Czech a break point. Rybarikova subsequently double faulted, which provided Kvitova a 5-1 lead. 

Serving for the second set, Kvitova fell behind 0-30 before three consecutive errors by Rybarikova handed Kvitova set point. A strong serve by the Czech was returned into the net, leveling the match at one set apiece.

Kvitova started the deciding set by holding the momentum, breaking Rybarikova in the opening game, then claiming an additional break for a 3-0 lead after a backhand lob by the Slovak fell just long.

Rybarikova clawed one break back in the following game, but then dropped serve once more at 3-1, after a big Kvitova forehand on break point forced an error from the Slovak. In the next game, a stunning backhand crosscourt winner by Kvitova pushed her to 5-1, placing her one game away from a successful title defense.

Rybarikova held serve for 5-2, attempting to put the pressure on Kvitova when serving for the match. But Kvitova was unfazed, and a backhand winner gave her triple match point. Kvitova only needed one chance, as an ace on her first opportunity sealed yet another trophy this season for the Czech.

"The important thing was that I break [Rybarikova] in the first service game in the second set," Kvitova explained. "I was little bit more relaxed. Same thing happened in third set. Probably those early breaks made me more relaxed then."