It was the eighth over of the Bangladesh innings after Pakistan had won the toss and chosen to field. Hasan, bowling the fifth delivery of the over, attempted a caught-and-bowled as his short-of-a-length delivery was chipped back towards him by debutant opener Tanzid Hasan. Hasan dived forward to take the catch, and fell awkwardly. The Pakistan team physio was out instantly, assessing Hasan, who was lying prone near the pitch. When he did get up, he looked a little dazed, and a stretcher was summoned to take him off. Salman Agha completed Hasan's over. TV footage showed Pakistan's fast bowling coach Umar Gul in discussion with head coach Sarfaraz Ahmed just when Hasan was being taken away from the ground, and it later emerged that Hasan was in the medical room at the stadium. There is no update on the exact nature of the injury. In case Hasan were to be ruled out of the Test, Amad Butt could make his Test debut - he is the only right-arm fast bowler among Pakistan's reserves in this Test. Shaheen Shah Afridi, who was part of the Pakistan playing XI in the first Test, was left out for this game in one of three changes Pakistan made after losing by 104 runs in Dhaka. Hasan took four wickets in that Test, including three in the second innings. Mohammad Isam is ESPNcricinfo's Bangladesh correspondent. @isam84