LAKELAND, Fla. -- When the radar gun at Joker Marchant stadium started flashing triple digits, Bruce Rondon's teammates took immediate notice of his work on the mound.

Joe Jimenez, fresh off his eighth-inning appearance, was watching through the fenced-off area from outside the clubhouse. Michael Fulmer, in street clothes, was looking on intently, too.

The 25-year-old flamethrower retired three straight batters, striking out both Jeff Decker and Luke Maile, and inducing a flyout from Richie Shaffer. Over the course of his stellar save, he hit triple digits on the radar gun three times. He hit 100 mph twice, and hit 101 as well.

"I think today was his best outing," manager Brad Ausmus said after the Detroit Tigers' 6-5 win over the Tampa Bay Rays on Tuesday.

Catcher Miguel Gonzalez said it wasn't only Rondon's velocity that was impressive but also his command. Rondon wanted to work on both his slider and his changeup, though he didn't get much opportunity to work the latter. He was able to locate exactly where he wanted with his fastball, Gonzalez said.

"His fastball command was great," said Gonzalez, who has also caught Rondon in Triple-A Toledo.

Ausmus said he couldn't tell from where he was sitting how acute Rondon's command was in the last inning, but he'll take Gonzalez's word for it.

"If Gonzo said that, that's a good sign," Ausmus said.

Rondon's sterling performance Tuesday was an encouraging sign in what figures to be a critical spring for the young reliever, who was sent home early at the end of last season because of "work ethic" issues.

Rondon entered camp aiming to put his past transgressions behind him and intent on winning a spot in a fortified bullpen. Only one or two spots remain following the offseason additions of closer Francisco Rodriguez, Mark Lowe and Justin Wilson. And Rondon might have a bit more to prove than others, considering the red flags raised with his theatrics last season, when he pout-pitched his way to an abrupt dismissal, a scene that did not go over well within the Tigers' clubhouse.

A more mature and professional Rondon is what the Tigers hope to find this spring, and so far, they've been happy with what he has shown.

"He's been good, he's done his work," Ausmus said. "He's taken his non-pitching fundamentals seriously, he's put in the effort, and he's looked strong so far on the mound."

In other Tigers news:

• Both Shane Greene and Daniel Norris, who are among the candidates competing for the fifth spot in the rotation, pitched Tuesday and were much happier with their performances as compared to their first outings last Thursday.

  "Right where I need to be," Norris said, despite giving up two runs and five hits in two innings.

  Norris said he used all four of his pitches and felt much stronger than he did against the Braves last week.

  "They all showed signs of being strong. I thought the ball came out of his hand a lot better than his first outing," Ausmus said. "It was jumping out of his hand more today, the fastball."

  Similarly, Greene was encouraged, save for the fastball that he left up for Rays designated hitter Kyle Roller, who went deep for a two-run shot.

  "I felt like my slider was better today than the other day," Greene said. "Really, it came down to one pitch, that one to Roller. If I could get that one back, it'd be a little different."

• Veteran second baseman Ian Kinsler and catcher Bryan Holaday are tearing up the first few weeks of spring training.

  Kinsler, who hit a two-run double in the second inning, leads the league with 10 RBIs in spring training, and his teammate ranks second with nine RBIs.

  Holaday, who is tied for the league lead with three home runs, was 1-for-3 with an RBI single Tuesday.

  "He's working his way towards the Grapefruit League Hall of Fame," Ausmus joked.