That’s the opinion of Arsenal legend Nigel Winterburn who believes the Spaniard has been pivotal to helping the Blues to the top of the Premier League table.
Costa is the top goalscorer in the top flight this season with 13 goals in just 17 matches.
Winterburn told Sky Sports: “I’m not sure who is more valuable but Costa for me fits perfectly into the way Chelsea play.
“If they were both out for a season then Chelsea would miss Costa more”
Arsenal legend Nigel Winterburn
“He’s just annoying isn’t he. He’s a fantastic goalscorer but he doesn’t give the back four or back five of the opposition any rest whatsoever.
“He’s harrying them, he’s always whispering in their ear, he’s niggling at them, he’s been absolutely sensational this season.
“He’ll work down the sides, the channels as well if he has to, I don’t think you’re going to see that from Ibrahimovic.
“Ibrahimovic is more a link-up guy and if he comes short I think what we’re seeing with Manchester United now is they’re having players run in behind him which they didn’t have in the earlier part of the season.
“It’s a massive debate but I would say if they were both out for a season then Chelsea would miss Costa more.”
Chelsea will be without Costa on Boxing Day as he is suspended for the clash with Bournemouth after receiving five yellow cards.
Ibrahimovic has also been in fine form for United, netting 10 goals in his last nine matches in all competitions.