Rhys Hoskins and Nick Williams had big hits, but L.A. avoided a sweep.
Sean Doolittle has never played a Major League game in Citizens Bank Park, but starred there in the Carpenter Cup.
"Professional is how I wanted to handle it," Joseph said. "I understand right now what needs to happen."
Therrien, 24, underwent Tommy John surgery earlier this week. He had an 8.35 ERA with the Phillies.
Aaron Altherr had four RBIs in his last two plate appearances to give the Phillies their third straight win against the best team in baseball.
The Phillies' young talent is ready to go, and they have a surplus right now, but it might be smart to stockpile some of it on the bench in 2017.
The rookie has yet to show his power stroke, but he has been getting on base.
He hit a bases-loaded double to the wall in left-center field to break the game open.
Scott Kingery and Tom Eshelman received the Paul Owens Award on Tuesday night and should reach the majors sometime in 2018.
The Phillies' Aaron Altherr hit the first grand slam ever given up by Dodgers ace Clayton Kershaw.
Chase Utley and the Dodgers could clinch the National League West at Citizens Bank Park.
Reliever Edubray Ramos surrendered a grand slam to Oakland's Joey Wendle Sunday, but the Phillies' bullpen still appears to be trending upward.
Maikel Franco went 3 for 4 on Sunday and drove in two runs in a 6-3 loss to Oakland. It was Franco's fifth multi-hit game since returning to the lineup on Sept. 8.
Wendle ripped a first-pitch slider from Edubray Ramos, almost bending down on one knee as he golfed it to right field.