Alonso is currently weighing up whether or not he wants to remain in F1 beyond the end of this year, when his current contract runs out.
He says his priority is to stick with Aston Martin, but he has also been linked with potential drives at Red Bull and Mercedes if certain scenarios open up.
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While the Spaniard has said he is more than happy at the team since he joined Aston Martin at the start of 2023, the squad has been battling in the middle of the chasing pack behind Red Bull this year rather than at the front of it as it was for a spell last season.
That has left team principal Mike Krack convinced the Silverstone-based outfit needs to up its game and push up the grid if it is to guarantee Alonso wants to remain.
"We need to add more, we definitely need to add more," said Krack. "But I think if he can fight and not be in the middle of nowhere, it's already a first step. And then we will not stop.
"We will bring parts over the season to keep him motivated and keep him happy at Aston Martin."
Aston Martin is coming off the back of an encouraging Japanese GP showing, where Alonso put in what he said was one of the best weekends of his career to bring his car ahead of both Mercedes cars and Oscar Piastri's McLaren.
And considering the Suzuka track puts a premium on tyre degradation like the season opener in Bahrain, where Aston Martin struggled, that has left Krack bullish about how things are lining up right now.
"I think we can agree that we were not in no man's land and then that is positive," he added. "Here with the high degradation…we seem to be in the pack. We were ahead of the Mercedes. So, that is very encouraging.
"But again, it's one data point. Bahrain is easier to pass than here, but we were never really under threat, let's put it like that. So let's see. We need to confirm over the next races."
Asked if he agreed with Alonso's verdict that the team had overachieved in Japan, Krack said: "Yeah. I kind of agree. Because when you look back, taking the first five races as a reference, we were, on average, the fifth fastest team, and maybe sometimes joint fourth.
"That means that you fight for seventh to 10th [positions], normally. When you have no quick cars out, and you finish in front of them, I think you have to agree with that statement."
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