Manchester City defender Eliaquim Mangala believes Raheem Sterling is destined to become a key player at the Etihad Stadium and will only get better in the years to come.

The England international has developed into an important part of the first team at City since joining the club from Liverpool ahead of the 2015-16 campaign and has already netted eight goals from 22 appearances in all competitions.

Sterling scored twice and set up another in the 4-2 Champions League win over Borussia Monchengladbach on Tuesday and Mangala is confident there is still more to come from the 21-year-old.

"He did really well for us on Tuesday and he's shown he can score important goals for us," Mangala told the official City website.

"He's a great talent and he wants to learn and keep improving and I'm certain he will."

Manuel Pellegrini's men clinched top spot in Group D following the results on Tuesday, but Mangala is not getting carried away just yet.

"It's good to finish top of the group, but we'll wait and see what happens in next week's draw," he added.

"You need to improve in this competition and you have to work to do that, but we feel we are learning all the time."