Leroy Sane is proving his worth to Manchester City all over again after Pep Guardiola decided the Germany international did not deserve to play on the back of a poor pre-season.

Sane followed a brace in the midweek EFL Cup win at West Brom with the opening goal against Crystal Palace on Saturday, adding a pair of assists as City ran riot after half-time to record a 5-0 win.

It was only the 21-year-old's second Premier League start of the campaign but he took his goals tally to five in all competitions.

Sane was one of City's leading performers during the second half of last season but surprisingly found himself below Raheem Sterling and Bernardo Silva in the pecking order when it came to Guardiola selecting the support attackers for strikers Sergio Aguero and Gabriel Jesus.

The former Barcelona boss told a post-match news conference that the answers lay on the training pitch.

"He didn't arrive good, he didn't make a good pre-season, he didn't deserve to play," said Guardiola.

"Now I have five strikers who all deserve to play. Gabriel Jesus is amazing, Bernardo Silva always creates, there's also Raz [Sterling], Leroy and Sergio…

"Some of them are going to rest. I need them sharp, especially in the second half of the season.

"But, of course, Leroy is so important for us. He's a guy who runs in behind in the right tempo, at the right moment as well as anyone else in the world.

"He is improving at the simple things, the simple balls, not losing the ball. Before he had to improve in that.

"Any goal is important and he is scoring a lot of goals, creating chances, giving assists. He is a young player, 21 years old, and he is so important for us."

City are top of the Premier League on goal difference after their latest resounding win – they are the first English team to win three consecutive top-flight games by five or more goals since Blackburn Rovers in 1958-59 – but Ruben Loftus-Cheek should have given Palace the lead before Sane illuminated a disjointed first-half showing with a brilliant solo effort.

Having rung the changes for Wednesday's trip to The Hawthorns, Guardiola felt his rested stars struggled to find their rhythm.

"We started good in the first five or 10 minutes, we created two chances and then after that we forgot that the ball should be moved," he said.

"When everything is slow, our rhythm is low, we concede counter-attacks and everything can happen.

"In the last 10 or 12 minutes of the first half before the goal, I felt we had it – moving the ball quicker – and we cannot deny that it helps a lot for Leroy to score in the last minutes.

"In the second half, we were what we have been in the last weeks. We had tempo, we were patient in the right moments and attacked quick when we could attack quick."

The only blot on City's day was left-back Benjamin Mendy limping off in the 29th minute with a knee injury that will be fully assessed on Sunday.

"Tomorrow we are going to make a real test," Guardiola added. "He feels better. It was a kick. Hopefully that's all.

"I don't know if the ligament is damaged. We are going to see."