Hearts will be missing defender Frankie Kent when they take on Celtic in Sunday’s lunchtime Premiership clash.
The game pits second in the league against third but Hearts will line up without one of their key players, after he suffered a knee injury in the midweek derby.
Kent has played every minute in the league as Hearts have cemented their place in the table.
Naismith admitted Kent would be missed but believes he has others who can grasp a chance to show they should be in his team regularly.
“Frankie obviously struggled at the end of the game against Hibs so he’s had a scan and he’ll be out,” he said. “We’ll miss him for a week or two.
“It’s disappointing but it’s better than what it could have been.
“Kye has obviously come back from the Asian Cup, we’ve got Toby and Stephen Kingsley has done well in there as well. We’ve got options.
“Frankie has come in and had a really good season. It’s shown that from the defensive side of our game this season.
“It’s disappointing to lose him but it creates an opportunity for somebody else to come in and show why they are part of the squad and why they should be part of the starting 11.”
Hearts go into the game against Celtic having drawn with Hibs in the Edinburgh derby in midweek but after suffering a bruising 5-0 loss to Rangers at Ibrox last weekend.
Naismith knows his side will face another tough challenge this weekend, with Celtic having roared back into form with a 7-1 win over Dundee on Wednesday.
“It’ll be a tough game,” he said. “They’re a good team and they’ve been the most successful recently.
“What they have got is experience. I’ve played with a few of their players and they have real experience. They’ve got a good squad.
“In the recent months it’s been tough of them and there’s been questions asked but they’re on the back of a good result.
“It’ll be similar to the other games we’ve had against them and, for that matter, Rangers. Last time we played at Tynie against them we were disappointing and we never hit the basic levels we needed and that’s something that must be different on Sunday.
“Being at home the atmosphere should be a good one, we should have the crowd behind us.”
The head coach has identified one major area for improvement but also takes confidence from Hearts overall form in recent weeks.
“I think what’s not been great for us in recent games has been in possession,” he said. “We’ve not kept the ball well enough.
“I didn’t feel we did that on Wednesday night. We did in the second half but in the first we were a bit quick to just clear it, we were quick to panic and out pass wasn’t right. That needs to be better when you play the best teams in the league.
“There’s a few things we want to be slightly better at but we go into the game confident. It’s one defeat in 14 and we’re in a nice position in the league.
“That’s come from our hard work throughout the season so I expect the same come Sunday.”
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