Signed as a free agent in the offseason, Percival has been perfect thus far in save opportunities, going 7-for-7. The 38-year-old right-hander has allowed just two hits and no runs this season over 11 innings.
However, in addition to the closer's dominance on the mound, Maddon has been impressed with Percival's influence on his predominantly younger teammates.
"He's got his way of including his thoughts into conversations that creates a stir among whoever is listening," Maddon said on Tuesday, noting that he was happy to see the veteran playing cards with a group of young pitchers before the game.
"He's got energy every day to carry on conversations," said Maddon. "A lot of [veterans] find it difficult to generate enough energy to carry on conversations on a daily basis, but he has no problem. That's just a part of his nature."
In terms of Percival's on-field impact, Maddon was amazed at the veteran's ability to take control of the Tampa Bay bullpen.
"I know what he does to the bullpen," said Maddon. "I know how he approaches it daily and refers to it as 'his bullpen.' I like it because he holds himself to a high standard as well.
"Whenever he goes out [to the mound], he puts it out there. And when he doesn't have success, he'll be the first to tell you. He's very accountable. A standup player. We needed that."
David Singh is an associate reporter for MLB.com This story was not subject to the approval of Major League Baseball or its clubs.