Mushfiqur smashed an unbeaten 219 of 421 balls, becoming the first wicketkeeper-batsman in history to score two double hundreds after he also played an innings of 200-run against Sri Lanka five years ago at Galle.
Sri Lankan veteran Sangakkara had scored as many as eleven 200-plus innings in his Test career, but only one of them -- 230 runs against Pakistan in Lahore in 2002 -- came in the dual role as wicketkeeper-batsman.
"I have said repeatedly, keeping helps me a lot," Mushfiqur told reporters.
"Though it doesn't mean that I will score centuries or double centuries in every match where I keep but it's my process, and I am a big believer in process and preparation," he said.
"It sometimes happens that there is a bit of a problem managing the workload of the two roles, but I think it is a challenge and the one which I always enjoy," he said.
Mushfiqur was stripped of his wicketkeeping job in the last three series, starting with South Africa tour in October 2017, after a costly blunder in a Test match against India at Hyderabad in the same year.
He returned to his favourite role in the ongoing series as regular Test wicketkeeper Liton Das was promoted up in the batting order in the absence of injured opener Tamim Iqbal.
"I am the kind of person who does not want to sit in the dressing room doing nothing," said Mushfiqur.
"I want to stay as much as possible on the field and contribute, feel like I am doing something for the team and my country."
On his way to his innings, the highest by a Bangladeshi overtaking Shakib Al Hasan’s 217 against New Zealand last year, Mushfiqur spent 589 minutes at the crease, which was another record for Bangladesh.
"Concentration is a matter of practice –- it does not come all of a sudden. So as I said, preparation is a big deal for me. And I try to practise in a way that is close to the match situation," said Mushfiqur.
Thanks largely to Mushfiqur’s innings, Bangladesh declared their innings at 522-7 before reducing Zimbabwe to 25-1 at stumps on the second day.
Bangladesh need to win to avoid a series loss after Zimbabwe thrashed the home side by 151-run in the opening Test in Sylhet.
Bangladesh vs ZimbabweBangladesh vs Zimbabwe 2018Liton DasMushfiqur Rahimrahimshakib al hasanZimbabwe vs BangladeshZimbabwe vs bangladesh 2018
First Published: November 12, 2018, 10:40 PM IST