The match fittingly concluded with a second-set tiebreaker, when up 6-5 and facing Isner’s serve, Federer returned a backhand that hit the top of the tape and dropped over helplessly to Isner’s side of the court.
Both players kind of shrugged, Federer with his usual grace and Isner with a good-natured smile.
The match lived up to its billing as one that would be dominated by service holds. Isner’s easy manner of bouncing the ball up to the line to ready his serve was like watching a gunslinger ready for a duel. There was plenty of dirt swirling around in the gusty winds, though tumbleweeds would have seemed out of place at Wimbledon.
Early in the first set, Federer and Isner traded serving holds, each feeling out the other’s serve.
Isner often came in behind his serve that Federer blocked back. He hoped to prevent Federer from controlling the rhythm on the baseline.
But Federer kept his concentration when the points were extended, and Isner often played for some tough winners that plunked into the net.
Federer also began to get better looks at Isner’s serve and forced his opponent into errors.
At 4-4, Federer pushed out to a 15-40 lead, but Isner saved both break points and took the advantage on a beautiful backhand drop volley.
Federer then forced a third break point and took it for the all-important advantage and a 5-4 lead.
As Federer looked to close out the set, Isner forced his own break point at 30-40 after a controlled up-the-line service return forehand that bounced on the baseline chalk.
The break point quickly vanished on Isner’s inability to keep an easy opportunity in play, and Federer closed it out on his second set point to win 6-4.
In the fourth game of the second set, Isner forced deuce after a great stab volley, but again Federer erased the opportunity with a pair of easy points.
The next game, Federer forced break point when Isner tried to approach the net. Isner slipped and fell into a sitting position and Federer’s return sailed over for 30-40.
Isner then responded with an excellent forehand into Federer’s deuce corner, and served out the next two points with a service winner and an ace to stay on serve at 3-2.
Federer continued to keep Isner off balance with excellent placement on his serving, cruising with a healthy 75 percent win rate on first serves.
Isner also held easily with big serves backed up by solid net play when needed.
They cruised into the tiebreaker, traded mini-breaks early on and set the stage for Federer’s backhand winner off the tape.
In the sideline postmatch interview, Federer said he had felt confident going into the match, and that he could create points and opportunities with his game. He also said he forced Isner into some mistakes, but that Isner had to take them.
Federer will now enter the medal round semifinal against Argentina’s Juan Martin del Potro, who advanced with his own 6-4, 7-6 win over Japan’s Kei Nishikori.
Federer holds a dominating 12-2 career advantage over del Potro and is the strong favorite to win on the fast grass. Federer defeated del Potro in straight sets at Wimbledon 2007, but did lose to him in the 2009 Barclays ATP World Tour Finals in London on hard courts.