Ashley Cole and Wayne Bridge are Capello's first and second choice in that position but injury to either of them for the tournament in South Africa would see England short of genuine contenders and Gunners boss Arsene Wenger said: "If Capello asks my opinion, I'll give a positive one. He's ready to step up."
Joleon Lescott or Matthew Upson could fill in at left-back but would not provide the pace of Chelsea defender Cole or his deputy in Bridge. Other options include Aston Villa's Stephen Warnock or Everton's Leighton Baines.
Arsenal veteran Mikael Silvestre, skipper for the win over Liverpool, believes youngsters such as Gibbs have matured and give Wenger the chance of his first trophy since 2005.
"We did quite well last season but know we have to step up a little bit and be more mature in our game," Silvestre said on BBC Five Live.
"I think all the lads learnt from last season and hopefully in March and April we'll be there to prove it.
"There are moments in the game when you have to hold your position or keep shape or make decisions. You only learn with experience and even young players like Jack Wilshere and Aaron Ramsey have shown they have matured their games from last season.
"The potential is high, we have everything to win titles here and it's up to us and the manager to prove it. We want to finish as winners not losers. We hope for a better future for us."