Sources said earlier this week that the contract is worth $4 million, plus another $1 million in incentives based on the number of starts Oswalt makes.
The 34-year-old former Philadelphia starter will join Triple-A Round Rock and is scheduled to make his first start on Saturday. Rangers pitching coach Mike Maddux said earlier this week that Oswalt will steadily build up his innings, throwing two or three on Saturday and then work up from there.
Oswalt said Wednesday that he believes he'll need around four starts. He said he's been throwing bullpen sessions every other day for the past six weeks to help get his arm in shape.
"My arm feels great, my body feels great," Oswalt said during a conference call with reporters Wednesday afternoon. "I think we'll go out and try to have a 50- or 60-pitch count that first game and I'm hoping after about four starts to be ready to join the team."
Oswalt said his back feels good and he's "as healthy as ever."