New Zealand opener Finn Allen has returned to the team bio-bubble after returning two negative Covid-19 tests on successive days. If Allen is available for the second T20I against Bangladesh on Friday, it will be a major boost for the visitors who were bowled out for 60 in the first game on Wednesday.

New Zealand head coach Glenn Pocknall welcomed back Allen although he said that the batter's condition has to be checked before a final decision on his selection is made.

"He has returned two negative results so that's great for us," Pocknall said. "He is a very attacking batsman. He has showed that around the world in the shorter format. He will add a lot of firepower to our batting line-up is a big part of our squad. Hopefully he can come into the squad as soon as possible. He will be considered (for selection) but it is a matter of when.

"He has just come off Covid so there are some unknowns about how he will be physically. He is fine now but we have to assess the affects in these conditions before we decide which game he comes back."

Allen and Colin de Grandhomme arrived in Dhaka on August 20 three days before the rest of the New Zealand squad as they were done with their Hundred campaign early. But Allen tested positive two days later. He showed some symptoms but was generally said to be doing well as he was quarantined in another part of the team hotel.

Allen tested negative on Wednesday and Thursday, to be called back into the side. He had made his T20I debut against Bangladesh earlier this year, hitting a half-century in the third game. Allen went on to play for Lancashire in the Vitality Blast, where he struck four fifties in 13 games. He played the Hundred for Birmingham Phoenix, making 165 runs in eight games.

New Zealand lost four wickets during the powerplay in the first game in Dhaka, with debutant Rachin Ravindra falling in the first over. His fellow opener Tom Blundell too didn't make much of a contribution, which could mean Allen taking his place.

Matt Henry, who was named as Allen's replacement, is finishing up his three-day isolation in the hotel, before joining the team on Friday, pending a negative Covid-19 test. Although not a like-for-like player, Henry's full vaccination gave him a place in managed isolation for his return to New Zealand, due to being part of the ODI squad to face Pakistan, which made him the logical replacement.

Mohammad Isam is ESPNcricinfo's Bangladesh correspondent. @isam84