In a full season, a major league starter is generally expected to go at least 200 innings of the course of the year.
Since Oswalt is pitching just half a season, 100 innings should be his goal.
Despite his injury history and the fact that he hasn’t pitched a major league game since last October, 100 innings seems a little far-fetched.
But with so many months of rest, the back that has ailed him over the past year has had plenty of time to heal, so those injuries shouldn’t be a problem.
Oswalt will have to average about 6.2 innings per outing, assuming he gets 15 starts. That is perfectly attainable for him if he can stay healthy.