Roger Federer became the first man to win 300 matches at the ATP Masters 1000 level, beating Vasek Pospisil 7-6 (7/4), 5-7, 6-2 on Wednesday in Cincinnati.
The victory in just over two hours put the 33-year-old world number three into the third round of his final tune-up tournament for the US Open.
The Swiss great, who had notched his 200th Masters match win against Lleyton Hewitt at Cincinnati five years ago, arrived at the tournament he has won five times off a runner-up finish to Jo-Wilfried Tsonga in Toronto.
He delivered a dominant third set to finally subdue the 46th-ranked Pospisil, who was a finalist last month in Washington. He stretched his career record over the Canadian to 3-0.
While Federer safely followed top seed Novak Djkokovic into the third round, three of the men's top nine were toppled.
Taiwan's Lu Yen-Hsun stunned Czech fourth seed Tomas Berdych 3-6, 6-3, 6-4 while Poland's Jerzy Janowicz upset number seven Grigor Dimitrov 6-4, 3-6, 6-3 -- four days after the Bulgarian played a semi-final in Toronto. American Steve Johnson stopped ninth seed Ernests Gulbis 6-4, 6-4.
Number five Milos Raonic was untroubled by wild card Robby Ginepri 6-2, 6-2.
Sixth seed David Ferrer fought through three tiebreakers to beat German Philipp Kohlschreiber 6-7 (4/7), 7-6 (7/4), 7-6 (7/4), and eighth-seeded Andy Murray advanced with a smooth, 6-3, 6-3 victory over Portugal's Joao Sousa.
Number 11 American John Isner beat Australian Marinko Matosevic 6-3, 7-6 (7/1), Fabio Fognini, seeded 15th, dispatched Lleyton Hewitt 6-1, 6-4 while number 16 Spaniard Tommy Robredo beat Sam Querrey 6-2, 6-4.
Women's top seed Serena Williams advanced on cue, downing Australian Samantha Stosur 7-6 (9/7), 7-6 (9/7), but third-seeded Wimbledon champion Petra Kvitova stumbled out of the gate.
Ukrainian teenager Elina Svitolina toppled the Czech 6-2, 7-6 (7/2). The defeat comes on the heels of Kvitova's third-round exit at Montreal in another blow to her build-up to the US Open -- the last Grand Slam of the year that starts on August 25 at Flushing Meadows.
Wimbledon finalist Eugenie Bouchard was another casualty, falling to Svetlana Kuznetsova in three sets.