A more relevant example might be Matt Clement, who destroyed his shoulder during his first All Star season in Boston, pitched through the pain, but was never the same afterwards.
Some have attributed his downfall to taking a line drive off the head. But by then his decline, while slow, appeared to have already started. In fact, his next starts after the line drive were actually better than the ones before it. Reportedly, an off-season evaluation of his shoulder revealed damage was far beyond what he should have been pitching through. But Clement, line drive and all, somehow managed 32 starts for the Sox that year.
Clement started 12 ineffective games for Boston the next season, and then never pitched in MLB again...