The advertising lights behind the baseline flashed and flickered, even while play was going on, and each time it made Andy Roddick more and more frustrated.
Finally, after being broken for the second time in the match, Roddick snapped. Or, actually, the rim of his racket snapped when he smashed it against his foot.
Roddick had been playing well through the first set, but shortly after wasting a pair of set points on Berdych's serve while leading 5-4, the eighth-ranked American was broken and eventually dropped the set.
In the second, Roddick held his first two service games relatively easily. Then, at 2-2, the neon lights on the front of the boxes where the line judges stand started to change, flickering red sometimes and then back to the light blue that they're supposed to be.
With Roddick growing increasingly frustrated, Berdych took a 15-30 lead with a forehand winner. Roddick then dumped a forehand wide on the next shot and lost his replay challenge, giving Berdych two break points.
After saving one when Berdych sent a forehand return long, Roddick tried an overhead smash from the baseline but the ball landed out, giving Berdych a 3-2 lead.
That's when he let it all out.
First, he whacked a ball high into the rafters — it eventually landed only three rows from the top of the lower section of the O2 Arena. Then, when he was walking back to his chair for the changeover, he smashed his racket against his foot and drew a code violation from the chair umpire.
"The neons in the back weren't quite to the settled position. They were still advertising fun stuff," said Roddick, who dropped to 0-2 at the round-robin tournament for the top eight players in the world. "When you're trying to track a ball, it's kind of neon lights and stuff. Then Tomas noticed it. A couple of them just went out before we played a point."
The match finished with the lights off.