Ralph Hasenhuttl praised James Ward-Prowse's ability to go from disaffected 19th man to Southampton's ever-present driving force.
Ward-Prowse, 24, has been touted for an England return after stringing together an impressive spell in the heart of midfield, scoring four times.
The dead-ball specialist has added steel and goals to his game and hasn't missed a minute since his recall to the side in late December.
Ralph Hasenhuttl praised James Ward-Prowse's transformation to Southampton's driving force
Yet Ward-Prowse was not in the squad for Hasenhuttl's third match in charge and admitted he considered his future under the new boss as he watched a 3-1 win at Huddersfield.
Hasenhuttl spoke glowingly of Ward-Prowse's reaction to that nadir.
'It was an interesting way he took since I was here. At first he was not part of the 18 at Huddersfield, so it was not easy for him,' he said.
'He took the chance, Mario Lemina was injured and Oriol Romeu was suspended and he got the chance to play at right back or in the No 8 and he showed what I was demanding from him he can bring on the pitch.
'That is the moment where you start to trust a player, where you start to get confidence with him and to accept he is a player that can help you.
Hasenhuttl spoke glowingly of Ward-Prowse's form and goalscoring exploits for the Saints
'He is young, he is physically very strong, he can play all three games in a week with a lot of running. That is no problem for him and that is a good basic of being successful in the future.' Ward-Prowse - who has made over 100 Premier League appearances - was also used sparingly under former boss Mark Hughes.
Ward-Prowse is top scorer from Hasenhuttl's 13 games in charge, and the Austrian praised his new-found goalscoring ability.
'I think it comes automatically because he is now more in a position where he has a chance to score. OK, to score outside