The two-time Wimbledon champion sustained serious hand injuries when an intruder broke into her apartment and attacked her last December.
Petra won 5 points in a row to notch a break, and she rattled off 12 out of the last 13 points to race over the finish line in style.
But American Coco Vandeweghe, who had looked in such strong form beating Johanna Konta in the previous round, had to retire with an ankle injury in her quarter-final against Spain's Garbine Muguruza.
"The hand is good, which is the best news I could have", she said.
But after losing her serve at the start of the second set, Safarova retired due to a thigh strain and exhaustion, having played two long matches in her previous three wins. I wanted to play my best, which I showed today and I hope I can keep doing it'. "It was just about one or two points and one or two breaks", said Kvitova.
It was the Czech leftie's first grass-court final since her triumph at 2014 Wimbledon and her 20th career title in her 27th final. But she remained reluctant to agree that she was now one of the players who could win Wimbledon.
Marin Cilic ended Gilles Muller's seven-match winning run on grass with a 6-3, 5-7, 6-4 victory to reach the final at Queen's tournament in London.
Mr America's Cup cheers for New Zealand
The crew quickly learned to sail the boat better and won eight straight races to complete one of the greatest comebacks in sports. The New Zealand camp have not said so far what they will do if they win the cup back.
Nevertheless, Petra was focused in game 9, bringing the set home with a comfortable hold, forcing the decider with the momentum on her side.
Breaks of serve were exchanged in the middle of the opening set, which Sevastova took, but Goerges fought back and broke in the sixth game of the second set before holding her service games to level up the match. I am happy that I am able to show good tennis here. "So this is quite a dream".
But she too double-faulted, repairing some of the damage with a brilliant passing shot which saved match point on Kvitova's serve at 6-4.
She sliced the ball hard, kept it wide and low, and denied Muguruza chances to develop pace and rhythm with her elegant groundstrokes. "She's such an inspiration", said the Australian.
"But I'm feeling confident, we've had a lot of grasscourt tennis now coming into Wimbledon, so hopefully we can play well tomorrow and transfer that through Eastbourne, and of course, Wimbledon". "I like slicing it around on the grass, and I didn't do much wrong".