Raheem Sterling's mentality is behind his prolific run of form for club and country, according to John Stones.

Manchester City winger Sterling netted a quickfire 11-minuite hat-trick after half-time on Tuesday as Pep Guardiola's side demolished Atalanta 5-1 in the Champions League.

Sterling also supplied the cross for Sergio Aguero's 34th-minute equaliser and won the penalty from which the Argentina striker put City in front.

Of his five career hat-tricks, Sterling has now claimed four match balls in 2019, including a brilliant treble in England's 5-0 Euro 2020 qualification win over the Czech Republic at Wembley in March.

"He's been on fire. He's got that mentality, he wants more," Stones said, before noting the one-on-one opportunity Sterling missed after completing his Atalanta hat-trick would probably disappoint the 24-year-old Ballon d'Or nominee. 

"He showed it [against Atalanta]. He kept trying, he might be disappointed because he could have scored four, but I think he should be very proud for scoring a hat-trick in the Champions League.

"I'm very happy for him and he helped us to take a step closer to the next round."

Sterling has 16 goals in 17 appearances for City and England this term – a flying start to the campaign that contrasts sharply with a 2019-20 yet to get off the ground for Stones.

The former Everton centre-back has been laid low for a month at a time following a pair of thigh injuries and only featured as a substitute against Atalanta and Crystal Palace last weekend despite midfielders Fernandinho and Rodri forming a makeshift centre-back pairing.

"Obviously, it's always frustrating going through injuries," he said.

"To me, it was a bit of a setback. Now I'm back, I feel strong and healthy again. Hopefully I can stay fit and help to fight for every competition."

Stones was introduced on Tuesday after Rodri pulled up with a hamstring injury, while his fellow centre-back Aymeric Laporte is recuperating from knee surgery alongside winger Leroy Sane.

City are waiting to find out the severity of another knee problem sustained by left-back Oleksandr Zinchenko, although Stones was at least able to line up alongside Nicolas Otamendi during the closing stages in midweek – the Argentina defender having shaken off a minor back complaint.

"It's been frustrating for all of us, for the manager, for the team, all the injuries we have got," said the 25-year-old.

"It's been a difficult time for us, but the guys have made a step up. They have done jobs for the team that they are not used to, so I give all the credit to them.

"Now, we [Stones and Otamendi] are back, we need to try to stay fit and healthy to help the team to fight for all the competitions."