How dependent are we on Mike Lowell?

Mike Lowell is prepared to hit the field and play in a game in two weeks, he reported yesterday. Although he hasn't suffered any setbacks with his right hip, he also hasn't been running the bases yet, which could make or break his progress.

It's very possible, although no noise has been made about it, that Lowell could suffer a setback which would either a) postpone his regular season debut or (worst case) b) knock his 2009 season out entirely.

Should Lowell not be able to start on Opening Day, this means Julio Lugo would start at shortstop with Jed Lowrie manning third base. There's a problem with this, however.