For the Bangladeshis, forced onto the back foot after being routed for 103 just after lunch on day one, Brathwaite's dismissal triggered their brightest period of play with the home side losing their last seven wickets for 68 runs.
While it was seamer Khaled Ahmed who initiated the slide by consigning the home skipper to his fifth ninety in Test cricket, Mehidy Hasan then stole the show in claiming four of the last six wickets to fall either side of the tea interval.
He also took a sharp catch at short extra-cover as Blackwood became the ninth wicket to fall in pursuit of quick runs.
However Mehidy's personal delight, and his team's cautious satisfaction at limiting the West Indies first innings advantage to a still considerable 165 runs, quickly dissipated when senior opener Tamim Iqbal and Mehidy himself fell to Alzarri Joseph.
That left Mahmudul Hasan and Najmul Hossain to carry the fight into the third morning.
Despite his excellent century against the same opponents in Chattogram 17 months earlier, the fact that the Bangladesh 'think-tank' felt it appropriate to send in Mehidy with more than half an hour's play available seemed a telling revelation on their own confidence, or lack thereof, in the resilience of the established middle-order batsman.
Not surprisingly, given that the pitch continues to offer some encouraging bounce and seam movement to the faster bowlers, Mehidy didn't last long, essaying his favourite forcing back foot shot but only succeeding in offering a straightforward catch to Kyle Mayers at first slip.
Joseph had removed Tamim in his previous over, the experienced left-hander drawn to follow a delivery angled across him for wicketkeeper Joshua da Silva to take the catch diving in front of first slip.
Bangladesh's precarious position was not for a want of effort from their bowlers.
With better support in the field and more judicious use of the available television technology, they could have significantly limited West Indies' first innings lead.
Both Nkrumah Bonner, who resumed as Brathwaite's overnight partner, and Blackwood were reprieved by on-field not out decisions when replays showed they would have been ruled out if captain Shakib Al Hasan had opted to challenge both decisions.
Bonner, who contributed 33 in a 62-run third-wicket partnership with Brathwaite, also edged Khaled at catchable height past a stationary Najmul Hossain at first slip before eventually ended his resistance by bowling him off the inside-edge in the visitors' only success of the morning.
The usually attacking Blackwood was even more pedestrian than his captain at the start of his innings with only three scoring shots off his first 43 deliveries up to the lunch interval.
None of this appeared to trouble the pair as they continued to plod along in the afternoon until Khaled, operating with the second new ball, got a delivery to jag back into Brathwaite and trap him so palpably lbw that not even the tantalising prospect of an 11th Test century just six runs away could prompt him into going for a review.