Maneul Pellegrini is looking to win the competition for the second time in three seasons as the Citizens take on Liverpool at Wembley.
The Reds were 4-1 winners against the Eastlands outfit in the Premier League earlier this season after an Eliaquim Mangala own goal and efforts from Philippe Coutinho, Roberto Firmino and Martin Skrtel.
However, former Liverpool skipper Barnes reckons Silva will have a big role to play in Sunday’s showpiece as the Citizens look to exact revenge for their heavy defeat at The Etihad.
“David Silva, for me [is City’s key man,” Barnes told Sky Sports.
“Sergio Aguero is the one who scores the goals but when Silva plays well, they play well.
“Yaya Toure and Raheem Sterling are likely to play too so once again, City might not necessarily look to one individual to win the game, either.”
Silva has scored two goals and has made eight assists in 24 Premier League games for the Citizens so far this season.
The Spain international was part of Pellegrini’s squad that won the Capital One Cup in 2014 after 3-1 victory over Sunderland at Wembley.
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