The defender was keen to depart in the summer, but no move materialised, and he has since played fairly regularly, as he scored in the 3-0 win over Cardiff at the weekend.
Peixoto has rotated between Krejci and Toti Gomes when Wolves have had a busy schedule with midweek games, but in recent weeks he has stuck with the Czechia captain.
The head coach insists Toti has done nothing wrong to lose his place, but says Krejci’s leadership, experience and tactical understanding mean he has been preferred.
Peixoto said of Krejci: “He’s important and a key player for us, he has a lot of experience, a lot of qualities, a player, a leader in the defensive line.
“He talks a lot, the teammates listen to what he says. He’s a clever, intelligent guy, he understands what I want from the defensive line.
“Sometimes I talk to him from the bench, he understands fast what I want.
“He’s an important player for us like the others, we have a lot of games and like we saw in the last two weeks, I rotated some players because I have confidence in all the players.
“Toti did an amazing job also, he didn’t drop from the starting XI because he didn’t play well, I have to take options because I have good players, and Krejci is one of those kinds of players, important players inside of the pitch.”