The decision to start Jennings is based on his preseason play and the fact that he has been at training camp, the source said.
The frustration from the Jaguars' brass over Jones-Drew's holdout is dying down, even if it appears the holdout was fruitless.
Jones-Drew finally met with coach Mike Mularkey on Sunday, a team spokesman told NFL.com and NFL Network's Steve Wyche. The two had spoken on the phone during the offseason, but not much since the start of the Jaguars' training camp.
"I had a really good visit this morning with Maurice and I welcomed him in," Mularkey later said in a statement. "It was good to finally speak face to face. I can tell he's ready to go, so we'll be working with him to get him up to speed as quickly as possible."
Jones-Drew will take a team physical Sunday.
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