(CNN) -- Marathon man John Isner gained revenge at the hands of his Wimbledon conqueror Thiemo De Bakker after knocking the Dutchman out of the Legg Mason Tennis Classic in Washington.
Isner lost in straight sets to De Bakker in the second round in London after his record-breaking win over Nicolas Mahout, from France.
The American's 6-4 3-6 6-7 7-6 70-68 win over Mahout at Wimbledon became the longest match in tennis history, stretching over three days and lasting 11 hours.
It was no surprise when an exhausted Isner was dumped out by De Bakker in round two but Isner got one over on his rival with a narrow win in the U.S. capital.
The match yielded only one break point but Isner couldn't take it. Instead he had to rely on two tie-break wins to triumph 7-6 7-6 and continue his decent run of form -- Isner was beaten by Mardy Fish in the final of the Atlanta Tennis Championships last month.
His record in tie-breaks this season is now 25-14 and his win set up a third round match with Belgian Xavier Malisse. After the match he claimed he hadn't been seeking to avenge his Wimbledon defeat.
"It wasn't like a revenge factor at all," he told the official ATP Tour website. "I treated it like any other match.
"It wasn't pretty out there. The only thing that kept me in the match was the way I competed. Not much was working right. Probably just the way I compete [got me through]. More times than not you're not going to play your best out there."
Isner was pipped in the 2007 final by fellow American Andy Roddick and the number two seed got his quest for a fourth Legg Mason title off to a winning start by beating Slovenian qualifier Grega Zemlja.
Roddick conceded just nine points on his serve in the entire match and made the most of his two break point chances to earn a straight sets victory.
"I accomplished what I wanted to," he told the official ATP Tour website. "I got into some rallies early and moved the ball around the court and mixed up paces and different heights.
"I put a high percentage of returns in the court and got back to playing clean tennis. Doing things that don't always show up on the stats sheet but they win you tennis matches."
Roddick was beaten in last year's final by Juan Martin del Potro in a third set tie-break and will now face world No. 6 Gilles Simon, who beat Russian Igor Kunitsyn 6-1 6-2 in just under an hour.
Elsewhere, number three seed Fernando Verdasco had a scare against German Michael Berrer before eventually battling through to win 4-6 7-5 7-6 and set up a tie with American qualifier Ryan Sweeting.
The number four seed Marin Cilic survived a clutch of break points to beat Uzbekistan's Denis Istomin 6-4 6-2 and book a date with American Mardy Fish.