Gymnastics: Reigning Olympic champion Shawn Johnson has announced her retirement from competitive gymnastics due to a recurring knee injury. The 20-year-old American has decided to call it a day on her attempted comeback and will not be defending her balance beam title at this summer’s London Games.

Auto Racing: Pole-sitter Scott Dixon won the IndyCar Detroit Grand Prix on Sunday, leading from start to finish in a race that was shortened from 90 to 60 laps due to peeling asphalt. Dixon beat the previous week’s Indianapolis 500 winner, Ganassi Racing team-mate Dario Franchitti, by 1.9628 seconds for his 28th career IndyCar victory.

Swimming: Michael Phelps won his final race before the US Olympic trials later this month, capturing the 200m ’fly for his third victory of the weekend at the Longhorn Elite Invitational. Phelps led from start to finish to win in 1min, 54.79secs with China’s Wu Peng second in 1:56.71 and American Neil Caskey third in 1:59.82.

Baseball: Comedian Bill Maher, a New York native and life-long supporter of the New York Mets, revealed that he has purchased a minority ownership stake in the Major League Baseball club. The 56-year-old television show host said he made the purchase months ago, but would not say for how much.

Rugby Union: Former All Blacks great John Kirwan, who has also coached Italy and Japan at Rugby World Cups as well as being an advocate for sufferers of depression, was honoured with a knighthood. The 47-year-old was named a Knight Companion of the New Zealand Order of Merit in the country’s Queen’s Birthday honours list for his services to mental health and rugby union.