The England skipper believes that there is reason to be optimistic as the squad look to recover from the 5-0 Ashes defeat in the winter, as well as continue to deal with the fallout from Kevin Pietersen's sacking.
"It's an exciting time for the international team in that, for the first time in a long time, there are quite a few places up for grabs," Cook told BBC Essex.
"That happens when you lose games and we lost five pretty heavily. Everyone knows this and good performances in the County Championship over the next few months will push people's claims. I don't think you rule anyone out."
Cook recorded a score of 181 for Essex against Derbyshire on Tuesday.