KEY BISCAYNE, Fla. -- Andy Roddick has been picking apart other people's predictions all week, fencing with reporters about how well they're doing on their Final Four picks.
Tuesday, he issued a long-range forecast on the rest of his season, which began with a lot of cloudy weather: Sunny, with a high chance of thundering first serves.
"The way I see it, my two favorite times of year are ahead of me,'' the fourth-ranked Roddick said after defeating feisty German qualifier Simon Greul 6-3, 3-6, 6-2 in the round of 16 at the Nasdaq-100 Open.
Those would be grass and hardcourt, specifically. "There's a lot of tennis left in this season,'' said Roddick, who won this tournament two years ago. "It's impossible for it to be a wash after two months.
"I can still play better. ... I think I'm playing a lot calmer now. I'm competing a little bit better. I'm not worried trying to win every point or win the match in every point. I'm kind of just staying a little bit even-keel and I'm serving 10 times better than I have been this year.''
ESPN commentator Mary Carillo agreed with Roddick's assessment.
"He needs a good run, and he could get one here,'' Carillo said after the match. "He's been losing these kinds of matches. He had to grub it out. He had to do that whole Alpha-dog thing, start barking and growling. You want to see a little foam at the mouth.
"He's been putting in the work and he needs to catch a break.''
Roddick is now 14-5 on the season. He hasn't reached a tournament final, and all of his losses have come to players outside the top 25, most recently in a round of 16 match to Russia's 29th-ranked Igor Andreev at Indian Wells.
After that defeat, the former world No. 1 told reporters he was baffled at the way he was playing and frustrated that he wasn't seeing any payoff for his efforts to develop a more balanced game.
"I used to like hit for a half hour and then go eat Cheetos the rest of the day, come out and drill forehands,'' Roddick said. Now I'm really trying to make it happen, being professional, really going for it, and I miss my Cheetos.
"I'm not the captain of Team Fun right now,'' he added later.
Roddick's quarterfinal opponent, 11th-ranked David Ferrer of Spain, is a strong clay-court player who logged a personal best record (16-11) on hard courts last year.
Ferrer's biggest challenge may be to recover from what he called "probably the tightest match I've ever played in my life,'' a three-hour, 18-minute victory Tuesday over Olivier Rochus of Belgium, the longest match of the tournament so far.
Roddick has played well if not brilliantly against lesser opponents at the Nasdaq-100.
The 24-year-old Greul, ranked 130th in the world, pestered Roddick throughout the match with a somewhat schizophrenic array of shots and a dissonant repertoire of groans and yelps.
"He plays some points where he just crushes every ball and then, you know, does the grunt thing,'' Roddick said. "Then some points he kind of stays back and doesn't really hit the ball. You don't know what part of him is going to come out in a point, really.
"I let him into the second set a little bit, then he started playing great toward the end of it. It's definitely a little bit of an awkward matchup.''
Greul beat No. 38 Paradorn Srichaphan of Thailand, No. 18 Dominik Hrbaty of Slovakia and Great Britain's No. 56 Tim Henman to reach the fourth round.
"I'm disappointed, but I see now that I can play at this level,'' the German said. "I think at the beginning of the third set [Roddick] pushed himself a lot and was very aggressive.''
The match featured one of the more interesting and theatrical challenges yet under the newly introduced instant replay system. With Roddick leading 4-1 in the third set, Gruel served an apparent ace on game point. The call was overruled by the chair umpire. Gruel challenged the overrule. The video showed that the serve was indeed good, and Gruel raised his arms in triumph.
As expected Tuesday, Roddick was named to the Davis Cup team that will play Chile in a second-round matchup April 7-9 in Rancho Mirage, Calif.
Davis Cup captain Patrick McEnroe sounded adamant as he fielded questions from reporters about Roddick's readiness.
"Let's be real here -- Andy Roddick has been a consistent top-five player or better in the last couple years, '' McEnroe said. "Has he had a tough stretch? Yes. Does he know that? Do I know that? Yes. Do I think he's right on the cusp of turning it around? Yes. Do I know his record from Wimbledon the last couple years? Yes. Are we playing this match on grass? Yes. That's a no-brainer.
"I love his work ethic. I love his intensity. I believe that it will come around. I believe that it might come around this week.''
Freelance writer Bonnie DeSimone is a frequent contributor to ESPN.com.