Boland slotted in for the injured Hazlewood in the second and final test against West Indies as well as the Proteas series-opener in Brisbane, which Australia won by six wickets.
He grabbed four wickets at the Gabba and is a specialist at his home Melbourne Cricket Ground where he celebrated a seven-wicket debut in the Ashes last year.
"We gave Joshy (Hazlewood) every chance, it just got to a stage where (he) more than anyone else felt like he was a little bit underdone," Cummins told reporters.
"It's a mark of the man really, he himself said 'don't feel quite right' so he kind of pulled himself out of selection. We talk a lot about how (as) a team we need a squad mentality and I think it's another great example.
"We didn't really get to the decision point, we gave it enough time and it played out. There would have been a part of everyone that would've felt a little bit aggrieved if Scott missed out."
Veteran batter David Warner (36) was also included in the team for the second test. He will become the 14th Australian to have played 100 matches in the format.
Australia completed victory at the Gabba in two days and take a 1-0 lead into the second test. The final match will be played in Sydney from January 4th.
Australia: David Warner, Usman Khawaja, Marnus Labuschagne, Steve Smith, Travis Head, Cameron Green, Alex Carey, Pat Cummins (capt), Mitchell Starc, Nathan Lyon, Scott Boland
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