New Zealand regained the ascendancy after a frustrating start to the second and final cricket test against Bangladesh by snapping a promising partnership and then dislodging another key batsmen during the middle session at Christchurch`s Hagley Oval.Trent Boult and Tim Southee combined to make the early inroads after Kane Williamson won the toss on Friday and the Black Caps pace bowling spearheads then emerged from a funk to spike a Bangladeshi resurgence.Boult severed an aggressive stand by denying Soumya Sarkar a maiden test century on his return from exile and then Southee claimed his second wicket to a leg side flick when dangerman Shakib al Hasan contributed to his own demise on 59.Sabbir Rahman, who made back-to-back fifties in Wellington, departed cheaply for seven - to Southee in the slips off Boult; Shakib then trudged off as Bangladesh lost 3-14 to slump to 179-5 and expose debutants Nazmul Hossain and Nurul Hasan.Fortunately for Bangladesh the rookies made it to the tea interval, carrying Bangladesh to 225-5; Nurul rode his luck to be unbeaten on 31 and Nazmul, who only has 12 first class games on his resume, was on 15 after he was summoned for his tour debut after Mominul Haque succumbed to a rib injury.Soumya looked on track to convert his first test fifty into three figures but a half-hearted drive was caught by a diving Colin de Grandhomme at short cover.One of three injury-enforced replacements following the Black Caps seven-wicket victory at the Basin Reserve on Monday, the 23-year-old emerged from a scratchy start to make 86 from 104 deliveries in his first test innings as an opener.Soumya and Shakib al Hasan - who amassed a record 217 in the first innings in Wellington - rejuvenated Bangladesh from 38-2 with a 127-run stand for the third wicket facilitated by bold stroke play, loose bowling and a fielding lapse when Soumya was on 56.Bangladesh resumed after lunch on 128-2 and continued to punish a Black Caps bowling attack that was starting to resemble the unit that had 595-8 plundered from it at the Basin Reserve last week.The satisfaction of snaring two experienced batsmen inside the opening hour was short-lived as Soumya, a first-time opener with only three previous caps and Bangladesh`s star allrounder peeled off runs at will. Bangladesh found the ropes 19 times before lunch and comfortably scored at better than four runs per over.They duo brought up their 50-run stand at a run-a-ball and three figures from 117 as a pace attack struggled with their line and length.The Black Caps fielding was also sloppy with Soumya give a reprieve on 56 when Jeet Raval dived in front of a set Ross Taylor at first slip and parried a de Grandhomme delivery to the boundary.Southee also grassed a regulation hip-height grab at third slip when Nurul - the wicketkeeping back-up for Mushfiqur Rahim - was on four - he was also the culprit when urging Kane Williamson to review an unsuccessful caught behind appeal against Mahmudullah when Boult was bowling.Boult claimed Mahmudullah in his next over, Bangladesh`s second setback inside the first hour after stand-in skipper Tamim Iqbal gloved a Southee deliver to BJ Watling.Southee and Watling used the same method to remove Shakib and in doing so became the most prolific bowler and wicket keeping combo in New Zealand history with their 44th dismissal overtaking the previous mark of Sir Richard Hadlee and Ian Smith.Soumya, who replaced Imrul Kayes (thigh), surpassed the 37 he made against India in his last cap in 2015 and ultimately stroked 11 boundaries in his 104-ball stay.Shakib`s 20th test half century was studded with nine boundaries, including three from de Grandhomme`s second over.Boult led the Black Caps with 3-63 from 17 overs; Southee (2-60 from 16) was the other wicket taker.Source: stuff.co.nz