The biggest surprise of the day was the defeat of former world number one, Serbian Novak Djokovic, who returned to the tournament following his elbow operation, only to be defeated by Japanese Taro Daniel, ranked 109th in the world, 7-6 (3), 4-6, 6-1.
Dimitrov continues to struggle in the California desert, the 26-year-old Bulgarian No. 1 never made it past the third round in seven appearances.
At the time Roger was trailing 5-8 in the head-to-head but in his own words: "That day I wasn't expecting to win".
Djokovic, a five-time champion at Indian Wells, now holds a 3-2 win-loss record this year.
Verdasco's first serve proved almost unplayable in the deciding set of the second round match as he improved his career head-to-head record against Dimitrov to 2-2.
Jack Sock has warned Roger Federer, Rafael Nadal and Novak Djokovic that their time at the top of men's tennis is about to come to an end as a new wave of younger players are ready to take over from the three that have dominated the game for over a decade. Less than 24 hours later, he was back on the court, where he finished off Federico Delbonis 6-3, 7-6 (6).
"The US Open final in 2004 comes to mind as the best match I've ever played, with the pressure of a Slam final", Federer said.
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Federer closed out the set on serve and pushed Delbonis to the brink of elimination in the process; however, he had to come back from a 15-40 deficit in order to do so.
Daniel sent an out-of-sorts Djokovic tumbling with a hard-fought 7-6 (7/3), 4-6, 6-1 victory.
Daniel, who beat Britian's Cameron Norrie in the first round, will meet Leonardo Mayer, who beat Ruben Bemelmans 6-4, 6-1.
"Very weird", Djokovic said.
"And not to mention as well, I've played so many tournaments as a kid here". While he targeted a comeback at the Madrid Masters in May, his quick recovery encouraged him to play at Indian Wells.
Federer said on Thursday that he won't be taking anyone for granted in this draw.
Federer will now play Filip Krajinovic in the third round. He's only going to get better from here. "Just didn't feel good at all, nerves were there".