LONDON - Manchester City centre-back John Stones says he is determined to repay manager Pep Guardiola for the faith he showed in him during his difficult first season at the Etihad Stadium. Stones, 23, produced several error-strewn displays last season after joining City from Everton in a £47.5 million ($62.9 million, 53.6 million euros) move that made him the world's second most expensive defender. But Guardiola stuck by the England international and has been rewarded this season as Stones has contributed to six clean sheets in City's last seven games, helping the club to top spot in the Premier League. "Really good," Stones said when asked how Guardiola had helped him last season. "Always positive and wanting me to do better and that's what I try to repay him on the pitch.