The seven free agents are right-handed pitchers Fernando Cabrera, Edwin Moreno and Jorge Sosa, left-hander Brian Shouse, infielders Angel Sanchez and Gil Velazquez, and outfielder Darnell McDonald.
Cabrera, Moreno, Sosa, and Shouse are all probably just there to be thrown into our giant pot of relievers try out for a spot- most likely they'll all end up in Pawtucket for callups should that become necessary.
Sanchez seems like he could be solid backup middle infielder depth (as we found out, there is never enough of that!). He's a pretty good fielder and has a pretty decent bat, though not much power.
Gil Velazquez will presumably be playing the same role he has for the last couple of years- last resort emergency backup SS/3B.
McDonald is a pretty obvious choice for a speedy outfielder pinch runner/defensive replacement. To me, he seems like the one with the greatest chance to crack the MLB roster, though really I wouldn't expect to see him up until September Callups.
It'll be interesting to see if any of them can make it, but as the roster is looking pretty solid already, it's probably going to be an uphill battle for all of them