Pep Guardiola's decision to strengthen Manchester City's defence has been the main reason for the Citizens' transformation into firm title contenders this season, according to former Newcastle United and City goalkeeper Shay Given.

The former Barcelona and Bayern Munich manager signed Claudio Bravo and allowed Joe Hart go out on loan to Torino. The Chilean struggled in his debut season at the Etihad and his poor form saw City concede in all competitions.

City finished fourth in the table, while failed to win silverware last season. The Catalan manager fixed his defensive woes by bringing in Ederson from Benfica, while strengthening the back four by signing Kyle Walker, Danilo and Benjamin Mendy.

This season, City are unbeaten in the Premier League and have won all three group stage fixtures of the Champions League. After nine games, they are leading the table with 25 points, five points ahead of second place Manchester United.

Given believes Guardiola has settled in England after a bit of struggle in his debut season and a solid backline will be crucial in their quest to win the title this campaign.

"Guardiola has strengthened this season in the defensive department. Three new full-backs and a new goalkeeper. I think that's important because the clean sheet record now is much better than last season," Given told IBTimes UK.

"And obviously, Guardiola has learnt from the last season. He knows it's a long winter, long hard winter and a long slog. He knows what to expect this season and more so the strength and depth in the attacking options is phenomenal.

"I don't have any fear that we will score in every game. Last season we were conceding too many goals and this year, we have tightened that up and that's a good recipe for a successful season."

Given also stressed that is is important for Guardiola to rotate the squad in December in order to avoid any fatigue-related injuries.

"It's important to rotate during Christmas time, probably to keep the team fresh. It's not easy because when you got a winning team, it is difficult to change that. You may want to keep that same XI," he explained.

"When you play Boxing Day on 26 December and play on 28 and then you play on 1, you are asking for trouble and injuries if you play the same team. Guardiola is a clever man and he knows that. It's all about rotating the squad at that busy schedule because there are so many games at that short period of time."

Pep Guardiola vs Crystal Palace
Pep Guardiola's Manchester City are on top of the table Getty Images