Mardy Fish may overtake Andy Roddick as top-ranked American tennis player

On the verge of victory, Mardy Fish took a lusty swing and staggered out of the follow-through, his left calf cramping and his ability to continue in doubt.

Three points later he limped into the quarterfinals, the last American standing at the Sony Ericsson Open at Key Biscayne, Fla. A gimpy Fish whacked a service winner on match point to win a grueling duel against Juan Martin del Potro, 7-5, 7-6 (5).

Fish is the lone U.S. player among the 16 men and women in the quarterfinals. At 29, he’ll overtake Andy Roddick and become the top-ranked American man for the first time if he defeats No. 6 David Ferrer on Wednesday.

Kim Clijsters overcame five match points to beat No. 19-seeded Ana Ivanovic, 7-6 (4), 3-6, 7-6 (5).

No. 21 Andrea Petkovic of Germany reached the semifinals with her second upset in two days, beating No. 6 Jelena Jankovic, 2-6, 6-2, 6-4. Petkovic eliminated No. 1 Caroline Wozniacki in the fourth round.

No. 2 Novak Djokovic extended his winning streak to 23 consecutive matches by beating fellow Serb Viktor Troicki, 6-3, 6-2. Djokovic has lost eight games in three matches.

No. 1 Rafael Nadal committed only five unforced errors and defeated No. 21 Alexandr Dolgopolov, 6-1, 6-2.

The U.S. men’s rankings face a possible shake-up because Fish’s longtime friend Roddick lost his opening match last week and is expected to drop from eighth to about 15th, the lowest he has been since 2002.

By contrast, Fish’s fortunes are on the rise. He’s ranked a career-best 15th and is into the Key Biscayne quarterfinals for the first time in his 12-year career.

Fiesta Bowl CEO is fired

The Fiesta Bowl fired its longtime Chief Executive John Junker after a scathing internal report released Tuesday found “an apparent scheme” to reimburse employees for political contributions.

Such reimbursements would be violations of state and federal campaign finance laws. The Arizona attorney general’s office is conducting a probe of the matter.

The Fiesta board of directors voted unanimously to fire Junker “for his improper and inappropriate activities documented” in the report.

Junker has been the face of the bowl for three decades, leading it from an upstart event to one of the BCS giants.

Elgin Baylor-Clippers case goes to jury

There was no verdict in Hall of Famer Elgin Baylor’s wrongful-termination and age discrimination lawsuit against the Clippers, owner Donald Sterling and team President Andy Roeser on Tuesday. The seven-man, five-woman jury will reconvene Wednesday morning to resume deliberations.

They were given lengthy instructions in Tuesday’s morning session and after lunch and were handed the case in the afternoon. Baylor, 76, was employed by the Clippers for 22 years in their front office, until 2008.

— Lisa Dillman

Boxer Andre Ward to pursue unified title at Home Depot Center

Unbeaten world super-middleweight champion Andre Ward of Oakland will continue his pursuit of a unified title May 14 at Home Depot Center when he faces Germany’s Arthur Abraham (32-2, 26 knockouts) in Showtime’s “Super Six” tournament semifinals. Tickets, priced at $25-$200, will go on sale Wednesday.

Ward (23-0, 13 KOs) has dispatched Mikkel Kessler and Allan Green in the tournament. The finalist who emerges May 14 will face the winner of the June 4 bout in Atlantic City between Carl Froch and Glen Johnson. Riverside heavyweight Cris Arreola (30-2, 26 KOs) will fight Nagy Aguilera (16-5) on the Ward-Abraham card.

— Lance Pugmire

Zenyatta no longer in foal

Zenyatta, the 2010 Horse of the Year, is no longer in foal after apparently having a miscarriage. She was bred to Bernadini on Feb. 23. An initial ultrasound had indicated she was in foal.

She is scheduled to be bred again to Bernadini next week.

— Eric Sondheimer

Phillies’ Lidge to miss first three to six weeks of season

Philadelphia Phillies closer Brad Lidge is expected to miss three to six weeks after an MRI exam showed he has a strained right shoulder.

Philadelphia General Manager Ruben Amaro Jr. said the reliever will not need surgery to fix the problem, deemed a posterior rotator cuff strain.

Pauley Pavilion to host NCAA tournaments in 2013

UCLA and a newly renovated Pauley Pavilion will serve as host of the 2013 NCAA championships in women’s gymnastics and men’s volleyball. The women’s gymnastics championships will take place April 19-21, 2013, and the men’s volleyball championships will be held May 2 and 4, 2013.

Pauley Pavilion is under renovation and reopen in fall 2012.

Jalen Rose arrested on suspicion of driving drunk

Former NBA and Fab Five standout Jalen Rose was arrested earlier this month on suspicion of drunk driving.

Lt. Tim Diamond of the West Bloomfield Township, Mich., Police Department said that Rose was arrested around 2 a.m. March 11. He’s accused of operating a vehicle while impaired.