The former Ireland international spoke to Off The Ball on Sunday
Munster suffered a deflating end to their season after a 24-point drubbing at the hands of Scarlets in the Guinness PRO12 Final.
Spectators at the Aviva Stadium watched on with disbelief as the Welsh side secured their championship status at a canter.
Speaking on Sunday's Off The Ball, former Ireland international Bernard Jackman analysed the Irish provinces performance.
"If you were a Scarlets fan you were enjoying every minute of it," he said. "But for the majority of Munster fans there, it was a nightmare.
"There was a level of shock at how Scarlets were able to get their scores so easily. They created five try-scoring opportunities and scored four of them. It's been an incredible end to the season for them.
"They play some incredible attacking rugby, but I think it's their defence that isn't getting the credit it deserves."
Jackman highlighted some of their defensive attributes which saw they overcome Leinster at the RDS and book their place in the PRO12 Final.
"Over the last two weeks in particular they've forced so many turnovers. After the Leinster semi-final, we were so critical of Leinster or felt maybe they weren't at the races mentally.
"But when you see what they did or Munster or what they did to Connacht a month ago, this is a team in peak form."
Munster players dejected after the final whistle at the Aviva Stadium. Image: ©INPHO/Dan Sheridan
He also pointed out that Scarlets' matchday nerves may have helped them overcome Munster. The side, he said, looked tense and "a little nervous" during the warm-up, but said these aspects of their game that they embraced.
"I don't think Munster were over-emotional. I would question whether they were as emotional as they needed to be. Seeing them walk out before the game onto the pitch, they looked incredibly calm.
"People talk about finals and enjoying the day and taking in the crowd. The reality is, if you don't get a performance, you don't win.
"Scarlets may have been stressed and were trying to stick to their routines beforehand, so be it. They made sure they dealt with the pressure of the 80 minutes."
Jackman said that Scarlets' unique style posed fresh problems for Munster.
"Not many teams play like that in the PRO12. Even Scarlets probably struggled to play like that in September.
"Scarlets are a team Munster really struggled against because they would be more used to teams who are direct. Normally Munster eat that up.
"The reason Munster defend so narrow is because it helps them dominate collisions and bully teams. Probably the majority of the PRO12 teams won't have had the skillset that Scarlets have."
There was still some positives to take from the season, however, and a second year under Rassie Erasmus looks set to bring the team more success.
"He'll add to Munster's attacking game. He took over a team low on confidence and brought a defence coach with him. He looked at improving their set-piece and their kicking game. And they did.
"They got a helluva lot more wins. They made progress. In year two you would expect they would want to add more to it."