SIMON Francis is adamant the absence of suspended duo Diego Costa and N'Golo Kante will not hit Chelsea hard and insists Cherries must be wary of the "unexpected" qualities of their potential replacements on Boxing Day.

Spain striker Costa is the top flight's leading scorer with 13 goals having started every league game this term, while ex-Leicester City lynchpin Kante is ranked in the Premier League's top five players for tackles and interceptions.

Neither player is available for the clash with Cherries at Stamford Bridge having both picked up their fifth bookings of the season against Crystal Palace on Saturday.

Blues boss Antonio Conte could turn to sparsely-used £33million summer signing Michy Batshuayi to replace Costa, while ex-Arsenal playmaker Cesc Fabregas could take over from Kante in the anchor role.

Reflecting on the absences of the Chelsea duo, skipper Francis told the Daily Echo: "Costa has been huge for them this season given the goals he has chipped in with and I'd say he's the best striker in the Premier League.

"Kante has been the buy of the season. Whoever got him in the summer was going to see a big difference in their team and he's certainly provided that since Chelsea have hit form.

"He's been excellent and that's two key players they are missing. Having said that, they have a brilliant squad. They have strength in depth and whoever they bring in is going to be a top player.

"We're certainly not thinking that because Costa and Kante are out that we've got a much better chance, because it's just not like that in the Premier League.

"If anything, we've got to be more aware because we've seen Costa and Kante play week in, week out so we know what they are about.

"When they bring in someone like Batshuayi who hasn't had too much game time, you have got to be more aware because it's the unexpected and it's the same with Fabregas.

"He hasn't played as many games as he would have liked but he has so much quality on the ball. It's something we'll have to address and try and stop him playing."

Conte's preferred 3-4-3 formation has been a revelation this season with Victor Moses among those to benefit, the former Wigan and Crystal Palace man receiving rave reviews for his performances down the right.

Defender Francis continued: "A lot of Italian teams have played three at the back over the years and Conte certainly did that when he was a manager in Italy.

"Although he didn't start with that in the Premier League, as soon as he changed to a three, it was almost as if something clicked and Chelsea have not looked back.

"It's interesting because it's brought out the best in some players who you haven't seen for years. Victor Moses has come out of nowhere and been excellent for them, so he is another player we will have to be aware of."