Kim Clijsters gave birth to her second child, Jack Leon Lynch, on Wednesday, both the retired Belgian tennis great and husband Brian Lynch announced on Twitter.
Jack Leon Lynch is born! Born at 7.06 pm tonight and we are both doing well... His big sister , mama and daddy are very proud and happy!¿ — Kim Clijsters (@Clijsterskim) September 18, 2013
Jack Lynch is born! Absolutely incredible. Mom @Clijsterskim is well and is my hero! Jada is an adorable big sis. What more can I say!! — Brian Lynch (@blynch8) September 18, 2013
Clijsters, 30, first topped the WTA rankings in 2003.
She had one singles Grand Slam title -- the U.S. Open in 2005 -- and two more in doubles -- the French Open and Wimbledon in 2003 -- before retiring in 2007 to start a family with Lynch, an American who played professional basketball in Europe for nine years.
Soon after the birth of their daughter, Jada Elle, in 2008, Clijsters returned to tennis and proceeded to win three more Grand Slam singles titles -- the U.S. Open in 2009 and 2010 and the Australian Open in 2011 -- and returned to the top of the world rankings.
She retired again last year after the U.S. Open.