After he was given his release, Papelbon said goodbye to teammates and already had some of his bags packed when the media entered the locker room after Friday night's game.
"It was a baseball decision. A roster move needed to be made when we needed our fifth starter for the first time in a couple of weeks," Rizzo said. "We went with what we felt was our best 25 players. … With the business of baseball, you have to cut a really good player, a really good veteran and a really good teammate like Jonathan Papelbon."
Papelbon, 35, was 2-4 with a 4.37 ERA and 19 saves for the Nationals this season. But his struggles nearing the non-waiver Trade Deadline forced Washington to acquire closer Mark Melancon from the Pirates.
"Pap was a professional. He never ran from anything. He faced the music whether it was good or bad. He handled it like a pro," manager Dusty Baker said.
Papelbon had a 2.56 ERA on July 23, but in his next five appearances, he allowed eight earned runs in 3 1/3 innings. After the team acquired Melancon, Papelbon was primarily used for mop-up duty.
"His command of his pitches was something he relied upon the last three or four years of his career. He was just missing his spots," Baker said. "When you miss your spots, you don't have blow-away swing-and-miss stuff like Pap hasn't had the last couple of years, you have to be very pinpoint and he wasn't."
Papelbon's teammates were sorry to see him go. Shortstop Danny Espinosa called him one of the best teammates he ever had.
"I love him. When he came from the Phillies, I wasn't sure. He was a guy I competed against," Espinosa said. "As he became a teammate of mine and I got to know him, I ended up becoming good friends with him. He has had a great career. I don't think his career is over. In his last outing [against the Giants] he was back up to 94, 95 [mph]. That was awesome to see."
The Nationals acquired Papelbon on July 28, 2015, in a deal which sent right-hander Nick Pivetta to the Phillies. At the time, the Nationals needed a closer because they didn't trust Drew Storen down the stretch. Papelbon didn't get many save opportunities in '15 because the bullpen struggled. Papelbon was also suspended for the final seven games of the season for trying to hit Orioles third baseman Manny Machado with a pitch and having an altercation with teammate Bryce Harper in the dugout.
After those incidents, Papelbon still had the respect of his teammates.
"He's not a distraction whatsoever. He comes here to play every single day," right-hander Max Scherzer said. "He works his absolute tail off and competes on the mound for us. All that stuff last year, that was just a media circus. We were a hundred percent behind him. We understood all of his intentions and he was great for our team. He was great for everybody in this clubhouse. To sit here and say he was a bad teammate or anything like that, it's garbage to me."
A six-time All-Star, Papelbon has a 2.44 career ERA and 368 saves in 12 seasons with the Red Sox, Phillies and Nationals.
As for Lopez, he returned to the Nationals for the third start of his Major League career. In 18 starts between Double-A Harrisburg and Syracuse this season, Lopez was a combined 5-6 with a 3.17 ERA. He leads Washington's Minor League system with 122 strikeouts and, among Minor League pitchers with at least 100 innings pitched this season, he ranks ninth in strikeouts per nine innings (10.73).