Roma captain Francesco Totti will be sidelined for at least 10 days with a hamstring injury.

Totti had to be replaced after 30 minutes in Friday's 2-0 win over Napoli with a right thigh muscle problem.

Michael Phelps has been working out with his former coach but there is no word yet on a return to swimming for the Rio Olympics.

Bob Bowman told The Associated Press on Sunday that Phelps has been taking part in workouts with the North Baltimore Aquatic Club. He's not yet committed to the sort of grueling program that would be needed if he decided to return to competition.

Japan's Mao Asada beat American Ashley Wagner on Sunday at Skate America despite a fall on her triple axel and a two-footed landing on her triple lutz.

Asada, the leader going into the free skate, scored 204.55 points thanks to her elevated technical difficulty. Wagner, the 2012 Skate America champion, finished with 193.81.

Arsene Wenger believes Arsenal's Champions League double-header against Borussia Dortmund will be "decisive" in the race to qualify from Group F.

Wenger's side host last season's runners-up on Tuesday before heading to Dortmund for the return on matchday four.

Serena Williams' verdict that she is "a bit disappointed" with her 2013 season indicates her urgency to overtake the 18 Grand Slam titles of Martina Navratilova and Chris Evert and to get on with chasing Steffi Graf's Open era record of 22.

Whether the 32-year-old still has time to achieve that may be suggested by her performances at the season-ending climax, the WTA Championships which starts on Tuesday.

Manchester United manager David Moyes has revealed star striker Robin van Persie is a doubt for Saturday's Premier League clash against Southampton.

Van Persie suffered a calf injury while in action for Holland against Turkey in midweek after previously suffering a toe problem before the international break and he is not certain to recover in time for the champions' meeting with in-form Saints at Old Trafford.

Roma captain Francesco Totti said he will undergo scans in the coming days after suffering a thigh injury in his side's 2-0 win over Napoli on Friday.

Roma's eighth win in as many games gave Rudi Garcia's men a five-point lead over Juventus in Serie A, although the Bianconeri can reduce the gap if they draw or beat Fiorentina away on Sunday.

Colombian goalkeeper David Ospina shrugged off his World Cup jet lag to star in Nice's 1-0 Ligue 1 win over Cote d'Azur rivals Marseille on Friday.

Ospina, who played in Tuesday's 2-1 World Cup qualifying win over Paraguay in Asuncion, pulled off a string of fine saves as Nice moved into fifth place in the table, four points off the lead held by Monaco.

Miralem Pjanic scored twice, once from the spot, to hand Roma a 2-0 win over Napoli and extend their lead in Italy's Serie A to five points on Friday.

Napoli, under the watchful eyes of former star Diego Maradona, began the match two points off the pace and hoping to upset Rudi Garcia's early season pacesetters.

Bayer Leverkusen snatched top spot in the Bundesliga on Friday but only after a "ghost goal" allowed them to beat Hoffenheim 2-1.

Leverkusen striker Stefan Kiessling looked to have headed wide in the 70th minute and even thrust his arms into the air in frustration at his miss.