Sports Digest/ Tennis: Former world number one Kim Clijsters announced her immediate retirement from tennis on her website yesterday.

Clijsters (23) has struggled with injury over the last few years and had said this season would be her last. The Belgian former US Open champion, who is getting married in July, had already pulled out of the French and US Opens.

"It has been more than great. The rackets will be hung up," Clijsters told her web diary (www.sport.be/kimclijsters).

She said recurrent injuries and the need to stretch for an hour every morning, along with preparations for her forthcoming wedding, had made it harder to carry on.

"Stopping aged almost 24 is pretty young but it has been wonderful. It would be easy to go on for a few more months and take in the four big earners in tennis," Clijsters wrote, referring to the remaining grand slams and the end-of-season Masters.

Although Clijsters won only one grand slam - the 2005 US Open - she reached four other finals and six additional semi-finals.

She also won the season-ender twice in a 10-year professional career highlighted by fierce rivalry with her compatriot Justine Henin.

"Money is important, but not the most important thing in my life. Health and a private life are more important."

Clijsters said last week she did not want to risk getting injured again and having to wear a cast at her wedding to the American basketball player Brian Lynch.

She added then that she planned to play at Eastbourne and Wimbledon in June. She had even mooted competing in the doubles at what would have been her final grand slam.

Yesterday's announcement means the Belgian played her last tournament in Warsaw last week, where she was defending the Warsaw Cup but looked short of form and lost in the second round to the Ukrainian qualifier Julia Vakulenko.

Clijsters had also committed herself to tournaments in Luxembourg and Stuttgart in late September and early October. She said she could yet attend, albeit from the stands.

Henin said yesterday Clijsters had been an important presence throughout her tennis career.

"I have a lot of respect for what she did in her career, as a player, as a person," Henin told reporters at the Warsaw Cup.

"We've almost grown up together and I think we've helped each other to come to another level because we pushed each other always to play better.

Stoner increases his lead

MotoGP: Ducati's Casey Stoner claimed his second win on the bounce to increase his lead at the top of the MotoGP championship with victory at yesterday's Chinese Grand Prix in Shanghai.

Stoner, who has won three of the four races staged this season, eased to victory after the Italian Valentino Rossi outbraked himself while trying to overtake the Australian for the lead on lap 16.

Fiat Yamaha rider Rossi survived his off-track excursion to claim second place at the chequered flag ahead of Rizla Suzuki's John Hopkins, who had started the race from second on the grid behind the pole-sitting Italian.

Stoner, who began the race from fourth on the grid, sees his advantage over Rossi at the head of the standings stretch to 15 points. Dani Pedrosa is third on 49 points.

Nicky Hayden's miserable start to the season continued when the reigning world champion was caught up in a first-corner crash that eliminated Toni Elias.

Hayden recovered to post 12th at the chequered flag.

Lakes victory for Meeke

Motor Sport: Kris Meeke and his Swedish co-driver Jonas Andersson in a Subaru WRC scored an impressive victory in the Ordnance Survey International Rally of The Lakes, their first win on only Meeke's third drive in a WRC car, Brian Foley reports.

It was down to youth versus experience in Killarney as a super-confident Meeke held off the challenge of triple Irish Championship winners Eugene Donnelly and Paul Kiely in another Subaru to win by 12.8 seconds.

Norwegian teenager Andreas Mikkelson (17) and Ola Floene were third in a Ford Focus WRC, in a repeat of their third-place finish on the Easter Rally.

Championship leaders Mark Higgins and Rory Kennedy never really got to grips with the stages of the southwest, but consistency paid off and they brought their Subaru home in fourth spot.

Yesterday brought the rain and treacherously slippery roads. The top three held their hard-won placings, and after the day's second stage at Ballaghbeama, a confident Meeke declared, "The guys have to catch me now."