Corbisiero - who grabbed the first try in the British & Irish Lions' third and decisive Test against Australia - then came off the bench in Saints' 21-20 semi-final victory over arch-rivals Leicester Tigers.
However, his recovery has come too late for England's tour to New Zealand next month with head coach Stuart Lancaster ruling Corbisiero out of contention.
With Vunipola also vying for minutes in the Red Rose front row, England has no shortage of depth at loosehead - but the Sarries wrecking ball insists Corbisiero would only strengthen what is already ferocious competition.
"I haven't really talked to Alex but I can only imagine what he has been going through," said Vunipola, speaking at the launch of the Aviva Premiership Rugby Policy.
"He has been really unlucky with injuries, getting knocked down every time he has come back.
"We have got a lot of good looseheads at the moment and I think that is only good for the team - that extra depth give us more options.
"You want to play for England but we also want to give each other competition and raise each other's game.
"That's the way rugby is nowadays - it's no different to me or Joe and one injury can put you back in the pecking order.
"For me it is about working hard and playing every game as though it's my last game."