Pep Guardiola says Sergio Aguero must prove he deserves a new Manchester City deal

All-time leading scorer is out of contract at the end of the season

Manchester City attacker Sergio Aguero under pressure from Gabriel of Arsenal during City's 1-0 win in the Premier League. EPA

Assistant referee Sian Massey-Ellis brushes off Sergio Aguero after the Manchester City striker put his arm around her during the 1-0 win over Arsenal at the Etihad. Getty Images

Raheem Sterling, second right, celebrates after scoring what turned out to be the winning goal in the first half against Arsenal at the Etihad Stadium on Saturday. EPA

Arsenal defender Hector Bellerin, left, and City attacker Sergio Aguero battle for possession.

Manchester City manager Pep Guardiola, right, and his Arsenal counterpart Mikel Arteta. EPA

Arsenal's Nicolas Pepe heads at goal. PA

Manchester City defender Ruben Dias. Getty

Arsenal's Bukayo Saka. EPA

City attacker Raheem Sterling holds off the attentions of Granit Xhaka. EPA

Arsenal captain Pierre-Emerick Aubameyang. Getty

City's Phil Foden sees his shot saved by Arsenal goalkeeper Bernd Leno. EPA

Arsenal new boy Thomas Partey, left, after coming on as a late substitute. PA

Manchester City manager Pep Guardiola says Sergio Aguero has to show he can still deliver on the pitch if he is to earn a new contract.

Aguero, who joined City in 2011 and is their all-time leading scorer with 254 goals, is out of contract at the end of the season and can speak to overseas clubs from January.

The 32-year-old sustained a knee injury in June and made his return in Saturday's 1-0 home win over Arsenal.

"Sergio now has to show, like every one of us, that he deserves to continue here - keep playing well, scoring goals and winning games - and after that the club and I will decide," Guardiola said.

"But if he's playing in his level we don't have any doubts that he's a player to stay until he decides because he's unique. He's important for us, our fans and everyone.

"But he was out four months and he has to start training regularly and start to score goals. Having Aguero on the pitch, we're better, safer. We missed him in the important moments at the end part of last season."

City, who are 10th in the Premier League with seven points from four matches, begin their Champions League campaign on Wednesday against Porto before a league meeting with West Ham United at the weekend.