"The risk of throwing him out there this weekend wasn't worth it," Black said.
Despaigne understood the decision.
"I've been doing therapy for it, working on my arm, I'm feeling much better. ... I did want to pitch, I was a little anxious to make my last start," Despaigne said through an interpreter. "But after the last time that I threw, it didn't feel right.
"I didn't feel that it was worth the risk of not being 100 percent when we're not playing for anything. If we were in contention for a playoff spot, I would have made a push for it."
Despaigne finished his rookie season with a 4-7 record and a 3.36 ERA in 16 starts and 96 1/3 innings -- all coming after June 23, when he was promoted from Triple-A El Paso. Despaigne, who signed a Minor League deal in May with a $1 million signing bonus, proved his worth quickly.
He tossed seven scoreless innings against the Giants and, four starts later against the Mets, came within four outs of the first no-hitter in franchise history. He had some ups and downs and was a much better pitcher at home (1.83 ERA in eight starts) than on the road (5.31 ERA, eight starts).
"I've had a lot of fun," Despaigne said. "I've enjoyed every minute of it. I've had my ups and downs. I've gave it my all. Sometimes they didn't go the way I wanted them to."
Despaigne hasn't decided if he will pitch this winter. If he does, the Padres have asked that he doesn't exceed 30 innings. Despaigne finished with a combined 128 innings in 2014 during his time in San Diego and two Minor League stops.
"He's thrown a lot of good games. This was a great learning experience for him," Black said. "I think the talent is there to be successful there. I think all in all, he showed very well. Going into next season, he had a leg up being in our rotation."
Corey Brock is a reporter for MLB.com. Keep track of @FollowThePadres on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.