Defending champion Djokovic fired his 15th ace on match point to defeat Querrey but his serve had been an issue earlier in their second-round encounter.
World No 1 Novak Djokovic kicked off his bid for a fourth Canadian crown with a 6-3, 7-6(4) second round win over a stubborn Thomaz Bellucci at the Rogers Cup on Tuesday.
Goffin stuns Federer to reach London final
Photos from Day 5 action at the Western & Southern Open at Cincinnati on Thursday.
Images from Day 4 of the Australian Open in Melbourne on Thursday.
On the men's side, the fields have already been divided into two ATP 250 tournaments.
Novak Djokovic recovered from a slow start as he continued the bid to retain his world number one ranking with a 4-6, 6-2, 6-3 win over 14th-seeded Bulgarian Grigor Dimitrov in the Paris Masters third round.
The top women's seeds continued to be scattered at Wimbledon on Wednesday, with Caroline Wozniacki's exit meaning five of the top eight were gone before the end of the third day.
'Remarkable discipline for training, competition, sacrifice, perfection, a little crazy but a legend of a bloke. Bravo Andy'.
A ruthless Sorana Cirstea took full advantage of Karolina Pliskova's patchy form at the China Open on Thursday, reaching the quarter-finals as she consigned the recently dethroned world number one to a 6-1, 7-5 defeat.
US Open, the final Grand Slam of the season, starts Monday, August 28, at Flushing Meadows in New York.
Olympic champion Andy Murray restored some order at the Western & Southern Open by cutting down South African giant Kevin Anderson to reach the quarter-finals on an upset-filled Thursday in Cincinnati.
Images from Day 6 of the French Open in Paris on Friday.
Having pulled out of the Brisbane International tournament through injury for the last two years, Maria Sharapova might consider it a victory in itself if she actually gets out on court at the Pat Rafter arena on Monday.
Roger Federer made a comfortable start to his quest for a 100th title, despatching Fabio Fognini in straight sets to ease into the quarter-finals at the Paris Masters on Thursday.
Tsonga outplayed his compatriot Adrian Mannarino 6-2, 6-2 in the opening round of the traditional Wimbledon warm-up event in his first match since suffering a four-set defeat by little-known Argentine Renzo Olivo at Roland Garros.
IMAGES from the Australian Open matches played on Friday.
World No 2 Rafael Nadal sailed into the quarter-finals of the China Open, his first tournament in 13 weeks, with a 6-3, 6-4 win over German qualifier Peter Gojowczyk on Thursday.
Serbia's Novak Djokovic is the top seed in the men's draw which includes five-times US Open champion and 17-times Grand Slam winner Roger Federer as seventh seed - his first time the Swiss has been placed outside the top three in a Grand Slam in over ten years.
Novak Djokovic and Serena Williams are top seeds at the major starting Monday
Halep through but Stephens exits in Cincinnati
Roger Federer became the latest big name to get sucked up by a whirlwind called Nick Kyrgios as the Australian tyro sent the Swiss top seed spinning out of the Madrid Masters in the second round on Wednesday.
Greek tyro Stefanos Tsitsipas' dream run at the Rogers Cup continued on Friday as the teenager toppled defending champion Alexander Zverev 3-6, 7-6(11), 6-4 to reach the semi-finals in Toronto.
Reigning champions Novak Djokovic and Serena Williams have been named top seeds for the Australian Open starting on Monday.
Defending champion Angelique Kerber battled her nerves and blew a match point in the second set before finally overcoming Lesia Tsurenko 6-2, 5-7, 6-2 to reach the second round.
Jack Sock became the first American to reach the last four of the ATP Finals in 10 years when he stunned world number three Alexander Zverev in a firecracker of a match on Thursday.
The spirit was as strong as ever but Rafael Nadal's troublesome knee failed him in the end as the Spaniard quit the ATP Finals after a painful defeat by Belgium's David Goffin.
A summary of Wednesday's action at the US Open.
Simona Halep will take over as the new number one in the WTA world rankings after progressing to the China Open final with a dominant 6-2 6-4 victory over Latvia's Jelena Ostapenko in Beijing on Saturday.
Nadal needed all his experience to keep Pouille at bay in the decider and the match looked to be heading for another tiebreak before he pounced to break Pouille's serve for the first time to go 6-5 up in the third.
Images from Day 7 at the US Open.
Rafael Nadal gave a much improved performance to advance into the quarter-finals of the Barcelona Open on Thursday, dispatching Spanish compatriot and crowd favourite David Ferrer 6-3, 6-3.
IMAGES from matches played on Day 4 of the French Open at Roland Garros on Wednesday
Jelena Ostapenko became only the sixth female Grand Slam champion to lose in the opening round of their title defence on Sunday when she lost to Kateryna Kozlova at the French Open.
Images from Monday's action at the Australian Open.
With the physical demands of modern-day tennis taking its toll the tournament will start without four of the top 11 in the ATP rankings including defending champion Stan Wawrinka who ended his season early with a knee injury.
A year after Andy Murray's reign as Wimbledon champion ended lamely at the hands of a man dubbed the new Roger Federer, he got a stark reminder on Friday that the original is the real threat to his grand slam ambitions.
Rohan Bopanna teamed up with Canada's Denis Shapovalov to enter the quarter-finals of the Rotterdam Open
Top seeds Novak Djokovic and Serena Williams face challenging early tests at the US Open following Friday's draws for the year's last Grand Slam starting on Monday.
Melbourne man McNamara won five singles titles and 19 in doubles and teamed up with compatriot Paul McNamee to win the Australian Open doubles in 1979 and Wimbledon twice in 1980 and 1982.
