Jimmy Connors is the other player to reach the milestone, and the American ended his career on 109 titles. "Welcome to the 'Triple Digit' tournament victory club," Connors said in a Twitter post to Federer, "I've been a bit lonely -- glad to have the company!!!"
By beating a player nearly half his age, the 37-year-old Federer continued his record of winning at least one title every season since his first in 2001 in Milan. Eight of his victories have come in Dubai.
"It's been a long, wonderful journey . I have loved every minute," Federer said. "It's been tough but the sacrifice has been very, very worthwhile and we'll see how much more I've got left in the tank.
"Reaching 100 is an absolute dream come true for me." As well as his record haul of Grand Slam titles, which includes a record eight wins at Wimbledon, Federer has won a record six ATP Finals and topped the rankings for a record 310 weeks — including 237 straight.
In a battle of the generations, Federer avenged his loss to the 20-year-old Tsitsipas, a rising star from Greece, in the last 16 of the Australian Open in January. Federer broke serve in the first game and took the set on his fourth set point.
The second set was more even, but Tsitsipas made the first big mistake in dumping an easy shot into the net to lose serve for a 5-4 deficit. His opponent then held serve to love to join Connors in the century club.
"I'm so happy I'm still playing," Federer said. "It all started as a junior world champion. It's been great. I wouldn't do it any differently."
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