That didn't make walking into the clubhouse the afternoon of July 28 any easier.
"I kind of felt like I had a couple heads walking in just because guys didn't really know how I was going to handle it," Storen said.
His pitching and the Nationals' season went into parallel tailspins. After converting on 29 of 31 save opportunities with a 1.73 ERA as the closer, Storen's ERA skyrocketed to 6.75 after Papelbon arrived from the Phillies.
Leading the National League East at the time, Washington went 31-33 after the trade and finished seven games back of the New York Mets. Even after Papelbon was suspended for initiating an altercation with NL MVP Bryce Harper in the dugout, the Nationals brought him back and traded Storen to the Toronto Blue Jays for outfielder Ben Revere.
Usurped as the closer by Papelbon's arrival, Storen isn't expected to go back to that role with the Blue Jays, either. But after two disappointing playoff outings, and after last season went off the rails and ended with a broken thumb for slamming the lockbox on his locker out of frustration, Storen is at peace with what happened.
"They are obviously not good things, but they're all things that made me better," Storen told The Associated Press on Wednesday. "When you get those challenges and you have to deal with that stuff, that's how you really make strides in this game. You can either sit around and feel sorry for yourself, or you can say, `You know what, I'm going to get better."
At 28 years old, Storen has been through a lot. He allowed four runs to blow the save in the deciding Game 5 of the 2012 NL Division Series against the St. Louis Cardinals. He was replaced as the closer by Rafael Soriano and then later Papelbon and endured another rough performance in the 2014 NLDS against the San Francisco Giants.
It would be easy to blame his struggles late last season on Papelbon's arrival, but Storen accepts responsibility for not handling the demotion well enough.
"It changed my role, so my workload got increased," Storen said. "No matter what your workload is, coming out of the bullpen you've just got to hit your spots and execute pitches, and if you leave it over the plate you're going to pay for it."
Storen wasn't surprised by the trade and said he was glad Toronto was the destination. But Roberto Osuna is favored to return as the Blue Jays' closer after picking up 20 saves last season, so Storen has to mentally prepare for another role -- and he sounds like he has.
"The seventh, eighth, ninth (innings), sometimes that's where the save happens because it's whoever's eating the teeth of the order," Storen said. "In reality if you're going to have a good bullpen, a championship-caliber bullpen, it's a group effort out there. It's not about one guy or a certain role."
While Rizzo felt trading Storen for Revere was "a deal (the Nationals) couldn't pass up," Blue Jays manager John Gibbons was thrilled to find out he'd have another strong, experienced right-hander out of the bullpen.
"He's been successful," Gibbons said. "I thought if we got one more top-notch reliever, which he's been, it was crucial to us. .... We feel good about him. Now we just got to figure out who's doing what and when."
Storen has experience getting shifted around, and Nationals lefty reliever Sean Burnett is confident his former teammate will thrive in Toronto.
"He's got a new opportunity, and I'm sure he'll take advantage of it," Burnett said Tuesday in Viera. "If he goes out there and pitches like he's capable of, obviously he can pitch in the ninth inning for any team. He'll be fine. He's got the personality and the makeup and the talent to get it done."
Storen doesn't lack confidence, saying his four-seam fastball and sinker and his overall ability to pitch are all better than they were years ago. Even though he was disappointed by how things went with the Nationals, he insists he's not trying to prove them wrong for choosing Papelbon over him.
"Everybody has their own job, and I'm not going to sit there and tell Mike how to run a baseball team because that's not my job," Storen said. "I'm concerned with what I'm doing more than anything. I want to win a championship because I want to win. It doesn't matter if I think people think I have something to show or prove. I don't worry about it anymore."