IANS
 
New York, Sep 2: Roger Federer cracked down at the first hint of trouble to see off tall, American danger-man John Isner in the US Open.

Top seed Federer, bidding for a fourth consecutive title at the last Grand Slam event of the season, on Saturday tamed the huge serve of US university star John Isner 6-7 (4-7), 6-2, 6-4, 6-2.

The Swiss world number one schooled the 22-year-old after losing the first set, dominating from that point onward.

"I was extremely happy with my reaction on the second set because the crowd was getting into it," said the winner of 11 Grand Slam events. "Losing the first set, it was a hard blow."

Isner now stands 0-2 against elite players after losing the Washington final last month against Andy Roddick, a 6-2, 6-2, 6-0 winner Saturday night over Swede Thomas Johansson.

Federer won his 23rd match at the US Open, where he was last beaten in 2003. The top seed dominated after the first set, with errors piling up as fast as aces for the youngster, who struck 18.

"The feeling of beating Roger Federer in a set, sitting down it was crazy," said Isner, who stands 6-foot 8-inches in his socks.

"I knew he was going step his game up. That's what he does every time he loses a set. He rarely loses two in a row. I knew I had to somehow keep it up for two more sets and unfortunately I couldn't do it."

Federer turned the screws after sealing the third set with an ace and breaking to start the fourth. The Swiss reached 4-1 as Isner's game faded.

"I was ready for a good player from the baseline as well," Federer said. "I will probably never be surprised on a tennis court because I don't underestimate opponents any more."