Ausmus announced the news Tuesday afternoon prior to Detroit's game against the White Sox at Comerica Park, and he said general manager Al Avila "completely agreed" with the decision. The manager declined to comment further.
"We have made the only comment we are going to make," Avila wrote in an email to MLB.com. "Brad and I met on Bruce and we both agreed this was the best course of action for Bruce and the Club."
Rondon pitched Monday evening during the Tigers' 3-2 loss to the White Sox in the nightcap of a split doubleheader. He tossed a clean ninth inning, though his fastball -- which routinely reaches triple digits -- hovered in the low 90s and topped out at 96 mph.
Catcher Alex Avila said Rondon -- who missed 2014 and the beginning of '15 as he recovered from Tommy John surgery and other injuries -- didn't give any indication that he was hurt.
"To be a big component of the team, you have to be here on the team," Avila said. "There's nothing else really for me to say. ... Put out your best effort every day, regardless of the situation."
According to Ausmus, relievers Alex Wilson and Neftali Feliz will likely earn the majority of save opportunities over the final two weeks of the season.
Rondon, who hails from Valencia, Venezuela, was signed by the Tigers as an amateur free agent in 2007. He will be eligible for arbitration in '17, and he is under team control through '19.
The righty impressed during his rookie campaign in 2013, when he posted a 3.45 ERA over 30 appearances and struck out 30 batters over 28 2/3 innings. Expected to become the primary setup man in '14, Rondon instead sustained a torn elbow ligament in Spring Training and underwent Tommy John surgery.
Though the Tigers anticipated Rondon would be ready to start the 2015 season, he didn't pitch at the Major League level until late June after starting the season on the disabled list with bicipital tendinitis. Frustrated at the speed at which Rondon's rehab had progressed, the club decided in May to have the reliever evaluated in Detroit under the supervision of head athletic trainer Kevin Rand and the club's medical staff.
Over 35 games with Detroit this season, Rondon posted a 5.81 ERA while issuing a team-high 5.5 walks per nine innings. When Joakim Soria was dealt to the Pirates at the end of July, Rondon became the club's primary closer in an apparent audition to secure the role for 2016.
"He's trying to do the right thing," Ausmus said Monday of Rondon. "He's still young and learning."
But by Tuesday afternoon, his clubhouse locker was empty.
Alejandro Zúñiga is an associate reporter for MLB.com. Follow him on Twitter @ByAZuniga.