Tamim and Mahmudullah show their Test credentials

It took until the final session on the second day at Chittagong for Bangladesh to produce their first disciplined display of Test cricket in this series, as Tamim Iqbal and Mahmudullah combined in a fourth-wicket stand of 94 that may not be sufficient to change the momentum of this match, but was nevertheless a timely reminder that the side really has been making progress in recent months. Their defeats may still be stacking up, but the small victories are starting to come about more frequently.

To call their stand a victory is still being charitable, however, because picking the positives out of the first two days of this match has involved as many forensics as your average LA homicide. When Mahmudullah lost his patience in the final half-hour of the day, to be caught off a top-edge by Paul Collingwood at slip, it left a gap in Bangladesh's defences from which they are unlikely to recover in a hurry, especially once Shakib Al Hasan had followed in the day's penultimate over, bowled by his own impetuosity as much as Graeme Swann's guile.

But all the same, Bangladesh can but soldier on and soak up the experiences, good, bad and downright ugly. Mahmudullah was one of their individual success stories from the recent tour of New Zealand, on which he made his maiden Test hundred while batting at No. 8, and today he showed the technical correctness and sufficient cool under fire to prove that his promotion to No. 5 is on merit, rather than out of desperation.

"I always enjoy my batting," he said. "The team want me to bat at No. 5 and I said ok, no problem, I can go for it. In New Zealand a couple of weeks ago there was a situation like this and we made a very good recovery. So I still hope we can make it in this Test as well. We have got our batting depth. Still Mushfiqur [Rahim] and Naeem [Islam] is there, and Tamim is still there. If we are able to bat properly we can achieve a good total."

Batting properly seemed alarmingly beyond their remit in the opening exchanges of Bangladesh's innings, however. For all the progress that Imrul Kayes has made in one-day cricket, with a century and two fifties in his 13 matches to date, his cluelessness against the short ball was alarming for an international opener. In 18 previous Test innings, Kayes' highest score was 33, and when Stuart Broad set to work on him, it wasn't hard to see why

In the space of three deliveries, Broad clanged a bouncer off Kayes' grille and away for four byes, tucked him up with a rib-tickler, and then extracted the limpest of pulls for Matt Prior to complete the dismissal. Junaid Siddique was scarcely any more comfortable with the ball spearing into his ribs, while Aftab Ahmed's credentials have been long under scrutiny. At 51 for 3 in the 12th over, a three-day finish looked to be on the cards.

But the gulf in class between Tamim at the top and Mahmudullah at No. 5 was as sizeable as the difference between their scores and the men sandwiched between them in the order. But on the evidence they produced today, not even the harshest judge could question the Test credentials that those two men produced. With the possible exception of Mashrafe Mortaza in 2003 and the 16-year-old Mushfiqur in 2005, their alliance was the most combative performance that England have yet encountered in the course of three Test series between the sides.

"Today we lost a couple of early wickets, two quick wickets for us, but Tamim and I had a good partnership, and I think we both enjoyed it," said Mahmudullah. "I am hopeful, the pitch is still good and I would say we had some poor shot selection. But Tamim is still at the crease and we have a good depth in our batting. I am hopeful that we will be able to avoid the follow-on and get a good score."

Tamim may need to stay at the crease for several hours yet to save Bangladesh from that fate, but the skill and maturity of his innings once again augured well for the future. By smoking Stuart Broad's first delivery through point for four he sent out a message that he would not be cowed, and it was reiterated soon afterwards when he lifted a Broad bouncer for six. But in between whiles he knuckled down to defend, for 84 dot-balls all told, while ever mindful of the chance to attack, as he did with 13 fours and a six.

"Tamim has been batting brilliantly, especially today," he added. "The moment he went out to the crease, he was positive from the beginning and played some very good shots. That was very good to watch. But since we have been playing on this pitch, we see it offers some turn on the first day and with every passing day it reduces and becomes flat. It is still like that, doing nothing extra. We have to come up with a very good batting performance tomorrow."