The Spaniard has finished third in all three races held thus far in 2023, and he has helped to lift the Silverstone team to second place in the current championship standings.
Krack acknowledged that the fact that the Aston Martin mechanics have sung Alonso's name beneath the podium indicated the esteem in which he had held.
"I think it was a confirmation basically, of where he's standing in the team," he said. "He brought a lot of energy, a lot of positiveness when he arrived.
"He is leading by example at all times. He's there very early, he's working really hard, and it is this lead by example that everybody just sees and grabs on and gives an extra level of motivation.
"And I think the singing of the name was like a confirmation also for him that he really brought a lot into the team."
Krack praised Alonso for his consistent form throughout race weekends.
"If someone told me you will have three podiums after the first three races I would have not believed it," he said.
"But it shows also what a champion we have there. He's just incredible, his consistency.
"If you look at all the sessions so far throughout the year he has always been there, in every session, in every FP1, FP2, he'll always up there and pushes the maximum all the time."
Krack downplayed the chances of Alonso being able to challenge for a third world championship in the coming years.
However, he insisted that age was not a factor.
"I think the most important thing is the speed and the desire to compete or the desire to be competitive," he said. "I don't like to speak about age, about Fernando's age, about my age also by the way!
"In general, I think it is really important how you keep yourself fit, how you keep yourself in, and what is your desire to do well, and this is something outstanding that Fernando is having.
"I would really be happy if we could provide the car for him to gain this third title, but I think we need to keep our feet a bit more on the ground, speaking about world titles.
"We have made now our first step in progressing from where we were before, and we should not start to dream."
Additional reporting by Alex Kalinauckas
