Manchester City boss Pep Guardiola has admitted he has failed to get the best out of Kalvin Phillips since signing him from Leeds United.
Phillips joined City from the Elland Road outfit in the summer of 2022.
Despite his £45m fee, the 27-year-old will start for only the fifth time for City when they take on Newcastle in the EFL Cup at St James' Park on Wednesday.
"Marcelo [Bielsa] gave Kalvin the best of Kalvin in his career," said Guardiola.
A hero at his hometown club, Phillips became an England international under Bielsa's stewardship when Leeds were still in the Championship.
He went on to become a key figure in the side that finished ninth on their return to the Premier League and then started for England as they reached the Euro 2020 final.
"I'd love to have done with Kalvin what Marcelo has done to him. We have our own specific way to play and [he] sometimes struggles in a few things, while the previous [Leeds playing style] was perfect [for him]," added Guardiola.
Phillips' lack of involvement is even more stark given two of his previous four starts came at the end of last season, after City had already secured their third successive Premier League title.
But with fellow holding midfielder Rodri suspended for three matches following his red card for violent conduct against Nottingham Forest, Phillips finally has a chance to play a meaningful role under Guardiola after turning down the opportunity to leave the club in the summer.
"The club spoke with him because he did not have many minutes," said Guardiola. "He said 'no, I want to stay'.
"We brought Kalvin here for his quality. He is open minded, always wants to learn and wants to help. This is what we want to try to do."
Guardiola revealed City will drive back from Newcastle on Wednesday night after encountering travel issues.
In the past, City have made the 150-mile journey from Newcastle by plane, but engineering issues and aircraft availability mean they cannot this week.
Guardiola appeared confused about the reasoning for what is likely to end up being a 3am return after the first of four away games in a row.
City face Wolves in the Premier League on Saturday before trips to RB Leipzig in the Champions League next week and to Arsenal on 8 October.
"I don't know what happened," said Guardiola. "The travel manager told me. We cannot come back by plane because we don't have a plane to travel back.
"We have to take a bus. It's not a problem but we arrive so late - two or three hours later."
Premier League clubs were criticised for using domestic flights last season because of their environmental impact.
BBC Sport researchfound evidence of 81 short-haul domestic flights made by teams to and from 100 matches during a two-month period this year, with some as short as 27 minutes.
Flights produce greenhouse gases - mainly carbon dioxide (CO2) - from burning fuel. These contribute to global warming.
Emissions per kilometre travelled are significantly worse than any other form of transport, with short-haul flights the worst emitters, according to the Department for Business, Energy and Industrial Strategy.