MELBOURNE, Australia (AP):

Australia cricket captain Michael Clarke was due to undergo surgery on his right hamstring today after doctors said he had sustained "substantial damage" to the tendon during the first Test against India.

After injuring his back on the first day, then returning the following day to complete a century, Clarke left the Adelaide Oval match during the final session Saturday, after he sustained his fourth hamstring injury in the past three months.

Team doctor for Australia Peter Brukner said yesterday, while "surgery is not always required ... Michael has substantial damage to a key part of the hamstring tendon. His recovery and the timing of his return to play will be dependent on the surgeon's advice and how well he recovers in the coming weeks."