Sunderland have revealed Steed Malbranque's chest pains stemmed from a muscle injury. The 30-year-old was taken to hospital after being substituted in Tuesday's 1-1 draw with Portsmouth. But the 30-year-old's health worries were put to rest the same evening as he was released after medical checks. "Steed has a musculo-skeletal chest problem for which he is receiving treatment," Sunderland physician Dr Glen Rae told the club's official website. "We are very grateful for the help of Portsmouth medical team, paramedics and Portsmouth local hospital for their help on Tuesday for arranging appropriate investigations for us." It is unknown how long Malbranque will be out of action, but the ex-Fulham footballer could be back in time for Sunderland's game with Arsenal on February 20.