India will lock horns with Bangladesh in the Asia Cup tournament-opener in Mirpur tomorrow. The Twenty20 match will start at 7 p.m. (IST). The continental championship will be played in a Twenty20 format for the first time, from the usual ODI, keeping in mind the World T20 to be hosted by India next month. Indian skipper Mahendra Singh Dhoni's availability is doubtful for tomorrow's fixture. He suffered a muscle spasm during the team's training session yesterday, prompting the BCCI to rush Parthiv Patel as his back-up. Hosts Bangladesh will be led by Mashrafe Mortaza.