"It was like someone puts a knife through your lower back," Janowicz said.
Janowicz is a volatile character, and that was on full display Tuesday. He pounded two balls in anger into the stands. He swatted one serve underhand. He chucked his racket. He argued with the chair umpire.
Other losers included No. 15 Nicolas Almagro, No. 25 Grigor Dimitrov and No. 28 Juan Monaco.
Federer says he doesn't fret about being seeded seventh at Flushing Meadows, a year after being seeded No. 1. Not since 2002, when he was 13th, had Federer been so low at the U.S. Open.
That didn't really affect Tuesday's opponent in Arthur Ashe Stadium. All that mattered to Zemlja, who owns fewer Grand Slam match wins, eight, than Federer owns Grand Slam titles, was that he was facing what he considered an impossible task.
"If he's the seventh seed or fourth seed or first seed, for me, that's totally irrelevant," Zemlja said. "He achieved so much. He's the best player of all time. So I don't think people can actually say something (negative) about the way he's playing. You're losing matches, you're winning matches — that's just tennis, and I'm sure he's going to perform better than maybe he has done in the last few tournaments."
Difficult as things have been for Federer, he certainly remains capable of summoning his best strokes. A bad lower back has bothered him this season, and he's experimented with a larger racket head, but with his old equipment in hand Tuesday, a healthy-looking Federer collected 35 winners and only 16 unforced errors.
Wearing neon-pink-and-gray shoes with a "5'' etched inside a silhouette of the U.S. Open trophy on the right heel — the number of titles he's won in New York from 2004-08 — Federer won 20 of the 21 points he played at the net and 62 of the 80 points he served. To cap the first set, Federer spun a 95 mph ace into a corner. To cap the second, he hit a 118 mph service winner that forced Zemlja into a backhand return so wild that it sailed directly into a guest box in the stands, where Federer's agent happened to catch the ball on the fly. And to cap the third, Federer pressed forward for a swinging forehand volley winner.
"I decided ... to play aggressive," Federer summed up. "I was happy the way I played, you know, overall. I mean, it's a first round, after all."
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