The 26-year-old Swiss star became the fifth-youngest player in history to reach 50, and only the ninth overall in the Open Era — since 1968 — to win so many tournaments.
Given the way he's playing, he's eyeing the U.S. Open as No. 51.
Federer almost got the noteworthy win a week earlier in Montreal, where he lost the title match to Novak Djokovic in a third-set tiebreaker. This time, he set the tone right away against the eighth-ranked Blake, who was playing in only his second Masters championship match.
Dressed in all-white on a muggy, 92-degree afternoon, Federer extended his mastery of Blake — and all Americans, for that matter.
Federer improved to 7-0 against Blake, who has won only one of their 19 sets — off a tiebreaker in the semifinals at the U.S. Open last year. He's not the only hard-hitting American who can't figure out how to handle's Federer's overall excellence.
Federer has won 35 straight matches against Americans since he lost to Andy Roddick in the semifinals at Montreal on Aug. 9, 2003, an astounding streak of dominance. During that span, different Americans have risen and fallen, but none has broken through.
Blake was playing catch-up right from the start. Federer served a pair of aces to open the match, then broke Blake's serve in the next game to take control. The 27-year-old American had three break chances in the fifth game of the opening set, which lasted 20 points and ended with Federer's emphatic forehand volley.
Opponents rarely get such chances against Federer. Deflated that he let it slip away, Blake was broken at 0-40 in the next game. Federer then served it out.
Blake overcame four double faults to hold serve in the opening game of the second set, but was on the defensive the rest of the way. Federer broke him to go up 4-3, then fought off a couple of break points in the next game to retain control.
Finally, he raised both arms in celebration after his ninth ace of the match gave him the title and, in his words, "a very special number."
Bjorn Borg won his 50th title when he was 23 years, 7 months old. Jimmy Connors was four months older when he got to the mark. John McEnroe and Ivan Lendl were 25 when they did it.
In recent years, the Cincinnati tournament has been a good barometer heading into the U.S. Open. Federer won it easily two years ago, then went on to get the second of his three straight U.S. Open titles.
Last year, Roddick emerged from his season-long funk in Cincinnati, won the tournament and took a lot of confidence into the Open, where he reached the title match before losing to Federer.
The Swiss star has momentum in his quest for a fourth straight U.S. Open title, but there's reason for others to see opportunity. Federer wasn't in peak form this week, making a lot of unforced errors. He needed three sets to beat Nicolas Almagro and resurgent Lleyton Hewitt to reach the title match.
Using that as a guide, this Open could be more wide-open.