LONDON (AP) -- The forecast calls for heavy showers at Wimbledon on Friday, which could create problems for a schedule that's already starting to become a bit jumbled.
If there is wet weather, the only arena that can be used is Centre Court, because it has a retractable roof.
As it is, two second-round men's singles matches were suspended in progress because of rain Thursday and scheduled to resume Friday, including 2002 champion Lleyton Hewitt against 2013 semifinalist Jerzy Janowicz. Play in their match was halted at 4-all in the second set after Janowicz won the first set.
Three singles matches were postponed before they even began Thursday, including 19th-seeded Feliciano Lopez of Spain against Ante Pavic of Croatia. The winner of that match will face ninth-seeded John Isner of the United States, who finished his second-round victory Thursday.
Here are five other things to look for at Wimbledon on Friday:
A COUPLE OF CHAMPS: A couple of past champions meet on Centre Court when Venus Williams plays Petra Kvitova. Five of Williams' seven Grand Slam titles came at the All England Club, most recently in 2008, while Kvitova won the tournament in 2011 for her lone major trophy. They're both hard hitters whose games are built for speedy grass - and their past matches have been quite close. Kvitova holds a 3-1 head-to-head lead, but all four lasted three sets, and each of the last two were decided by tiebreakers.
WINNING STREAK: Defending champion Andy Murray takes a 15-match winning streak at the All England Club into the third round against 27th-seeded Roberto Bautista Agut of Spain. Murray won six matches in a row at the place to earn a gold medal at the 2012 London Olympics, then seven in a row during Wimbledon last year en route to the title, plus another two so far this year. ''You're going to get tested during the tournament. Sometimes that happens in the first round, and sometimes it can happen in semifinals,'' Murray said. ''It can happen at any moment in the tournament. You just have to be ready for it and expect it before every single match.''
ANOTHER SURPRISE?: Portugal's Michelle Larcher de Brito could create problems for 2012 runner-up Agnieszka Radwanska on Court 2. The 21-year-old Larcher de Brito made a mark last year at Wimbledon, when she eliminated 2004 champion Maria Sharapova. She is ranked only 102nd, so she had to qualify for the tournament, but Larcher de Brito already won a pair of three-setters to get to the third round, including beating two-time major champion and 28th-seeded Svetlana Kuznetsova.
FINED FOGNINI: Fabio Fognini, an Italian seeded 16th, plays his first match since finding out he'd been docked $27,500 by Wimbledon for unsportsmanlike conduct and what the tournament termed a visible obscenity during his first-round victory this week. Will he be on his best behavior against No. 20 Kevin Anderson of South Africa on Court 17?
BRYANS START: Defending men's doubles champions Bob and Mike Bryan are scheduled to play their first-round match against Matthew Ebden and Samuel Groth, which was on Thursday's schedule originally but got postponed. The Bryan twins, who are seeded No. 1, did not reach the final at any of the last three Grand Slam tournaments - after winning four major titles in a row before that, starting at the 2012 U.S. Open.
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