Indian Wells competition heating up

Now that the business end of the tournament has officially arrived, this edition of Five Things We Learned carries the utmost urgency.

1. The Champ Stays The Champ

In the first set, Flavia Pennetta was having something of a crisis. The moment was big, she wasn't happy with the way she was playing, and she broke down on the court, shedding tears. Maria Sharapova took advantage, winning the final three games of the set. Then Pennetta, the 15-seed and the defending champion who beat Aga Radwanska in the final last year, started ripping her backhand, outhitting Sharapova, which doesn't happen often. She took the second set 6-3, and then ousted the No. 2 seed in the third 6-2.

"No, no. Panic attack, no," Pennetta said. "Just a lot of emotion in one night. Sometimes a woman has these moments, so I was trying to handle it. I just breathe and let it pass, and in the end it was much better."

2. Roger Rolls On

Andreas Seppi was 0-for-11 against Roger Federer until they met at the Australian Open in January and Seppi stunned him. They met again in the third round here, and the result was a much more routine 6-3, 6-4 Federer win. Federer reached the final here last year when he lost an epic three-setter to Novak Djokovic. American Jack Sock awaits the four-time champion in the fourth round.

3. An American Mixed Bag

Serena Williams remains, but she had to knock out fellow American Sloane Stephens to do it, leaving one American woman left in the draw. For the men, Rafael Nadal defeated Donald Young and Tomas Berdych beat Steve Johnson, leaving two Americans. John Isner will play Novak Djokovic in the fourth round on Wednesday, and Jack Sock upset 15th-ranked Roberto Bautista-Agut in a three-set comeback win. Isner was a semifinalist last year, but the story is Sock, who appears more comfortable as a doubles player but has the kinds of weapons -- a 130 mph serve and a massive, heavy forehand -- Americans haven't seen since Andy Roddick. I rated Sock a "buy" on my preseason stock portfolio, and this kind of run at a Masters 1000 is the reason why. He will play Roger Federer in the next round. Sock, meanwhile, is also alive in the doubles, where he and partner Vasek Pospisil of Canada will play the Bryan Brothers, whom they beat in the Wimbledon final last year.

4. Rafa Starting To Feel It

He complained about the conditions and the poor quality of the tennis balls, but after an uneven start, Nadal beat Young 6-4, 6-2 to advance to the fourth round. The Nadal positives -- efficient service games, slashing inside-out forehands -- were in place, except for a high unforced error count, which he in part attributed to hard daytime conditions. After his win, Nadal said the felt as well as he has felt, a sign he is reaching some comfort with his game. Nadal will play Gilles Simon, who beat German Michael Berrer. Nadal, who has won this tournament three times and also in doubles in 2012, is alive in doubles, too.

5. An Aussie Will Reach The Quarters

After defeating Nadal at Wimbledon last year, Nick Kyrgios was all the rage, but tennis people kept reminding folks not to sleep on the other K: Thanasi Kokkinakis. Kokkinakis is alive and plays countryman Bernard Tomic on Wednesday in the fourth round. An investment in an Australian Davis Cup team of huge servers and huge talents Tomic, Kokkinakis, and Kyrgios isn't a bad idea.