|Fish, here winning his third-round match, withdrew from the U.S. Open Monday. (AP)|
And Murray served rather well himself, too.
Still seeking his first Grand Slam title, Olympic champion Murray reached the quarterfinals at an eighth consecutive major tournament by beating 15th-seeded Raonic 6-4, 6-4, 6-2 on Monday night.
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The third-seeded Murray converted 4 of 12 break points and never faced one. After weathering six aces across Raonic's first three service games, Murray only allowed eight the rest of the way.
"You start to see things after a few games. He started serving a lot of big serves. I was just trying to react as quickly as possible," Murray said in an on-court interview at Arthur Ashe Stadium. "Sometimes they fly past you, sometimes you get a racket on them - and I got a racket on them."
Raonic's 14 aces were less than half as many as he accumulated in any of his first three matches this year at Flushing Meadows, when he hit 30, 30 and 29.
"I used a lot of variation tonight. Milos has a huge game, massive serve. I had to guess on some of the serves," Murray said. "I got lucky a few times."
Next for Murray is a match against No. 12 Marin Cilic. Murray leads their head-to-head series 6-1, but his only loss to Cilic came at Flushing Meadows in the fourth round in 2009.
"Really interesting for me. Another big challenge. Andy's obviously playing really well," Cilic said after his 7-5, 6-4, 6-0 victory over 50th-ranked Martin Klizan of Slovakia earlier Monday.
"When I feel well," Cilic added, "I feel I can match up with anybody."
Murray probably thinks the same way, especially with the confidence boost he picked up with his gold medal last month.
He's yet to win the last match at a Grand Slam tournament, though: Murray and his coach, Ivan Lendl, are the only men to lose their first four major finals.
Murray only had played once before against Raonic, who was trying to become the first Canadian man in a major quarterfinal in the Open era, which began in 1968.
Going in, it appeared to shape up as an intriguing matchup, pitting Raonic's tough-as-can-be serve against Murray's good-as-it-gets returning skill and pinpoint passing shots.
Raonic entered the U.S. Open leading the ATP in several key serving-category percentages - service games won (93), first-serve points won (83), break points saved (75) - and second in total aces only to 6-foot-9 American John Isner, who lost in the third round in a match that ended at a tournament-record-tying 2:26 a.m. Monday.
Murray, meanwhile, tops the tour in points won returning second serves (56 percent) and is fifth in return games won (31 percent).
Giving himself a better chance at dealing with Raonic's speedy offerings, Murray stood way, way back behind the baseline while preparing to hit returns. And that worked, allowing Murray to blunt Raonic's serves that consistently arrived at more than 130 mph.
On the very first point, Murray got back a 120 mph serve and then delivered a backhand passing winner down the line, a sign of things to come.
At 4-all, Raonic gave away two points with a pair of double-faults, and Murray broke for the first time by carving a drop shot at a tough angle that the Canadian couldn't get to. Showing he can sling it, too, Murray served out the set with a 138 mph service winner.
Murray won 20 of 24 points on his serve in the first set. He capped the second with an ace that clipped a line, and ended things with a 129 service winner on match point.
The 30-year-old American, who was seeded 23rd at Flushing Meadows, missed about 2½ months this season because of an accelerated heartbeat and had a medical procedure in May.
"We are not 100 percent sure what the issue is and if it is related to his previous issues," Fish's agent, John Tobias, wrote in an email to the Associated Press. "Mardy is fine and will return home to L.A. tomorrow. This was strictly precautionary and I anticipate that Mardy will play in Asia this fall."
Fish's departure means 2003 champion Andy Roddick is the only American man left in the field. Roddick, who announced last week that he'll retire after the U.S. Open, plays 2009 champion Juan Martin Del Potro in the fourth round Tuesday night.
Fish's third-round victory over Gilles Simon at the U.S. Open went five sets, lasting more than 3 hours and ending after 1 a.m. Sunday. Afterward, Fish did not attend a news conference; the tournament said he was getting medical treatment, but didn't elaborate.
In a statement released by the U.S. Tennis Association on Monday, Fish said he "was reluctant to" withdraw from the year's last Grand Slam tournament but was "following medical advisement." He added that he looks forward "to resuming my tournament schedule in the fall."
After losing a match at Key Biscayne, Fla., on March 29, Fish went to be checked by doctors because his heart started racing uncontrollably that night. He pulled out of the U.S. Davis Cup team's quarterfinal against France the following week.
In May, doctors induced extreme palpitations to try to pinpoint the problem in Fish's heart. He returned to the tour at Wimbledon in June.
The walkover allowed the top-seeded Federer to reach his 34th consecutive Grand Slam quarterfinal, extending his own record.
"I am really sorry for Mardy. I just want to wish him a speedy recovery," Federer said in a statement issued by the tournament. "We all want to see him back on tour soon."
Federer, who has won five of his record 17 Grand Slam titles at the U.S. Open, can reach the semifinals by getting past No. 6 Tomas Berdych of the Czech Republic, who eliminated No. 11 Nicolas Almagro of Spain 7-6 (4), 6-4, 6-1.
Berdych stunned Federer in the 2010 Wimbledon quarterfinals on the way to reaching the final there.
"It will be a tough match against Tomas. We have played many times in the past and he has always been a tough opponent," said Federer, who has won 11 of 15 career head-to-head matchups. "I will have to continue to serve well and dictate the points."