Ipswich Town manager Paul Lambert hasn’t ruled out a free agent signing following the news that striker Freddie Sears will be sidelined for up to a year with the knee injury sustained in Sunday’s East Anglian derby 3-0 defeat at Norwich City.

That leaves Lambert with Will Keane, Collin Quaner, Ellis Harrison and Kayden Jackson as forward options for the remaining 15 games.

The transfer window for permanent and loan additions may be shut, but clubs can still sign free agent strikers with the likes of Darren Bent and Gabby Agbonlhaor currently unattached.

“If somebody is a free agent now there is something wrong,” said Lambert, whose side – nine points adrift of safety at the foot of the Championship table – take on Derby County at Portman Road tomorrow night.

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“I don’t know, I really don’t know. I’ll go with the lads I’ve got at the minute.

“You can never say never or what’s around the corner though.”

On Sears’ set-back, Lambert said: “I never expected to come in yesterday morning to be told that.

“Do you know, I’ve never been at a club where I’ve seen so many long-term injuries. That’s Freddie ALC, Wardy (Grant Ward) ACL, Ben Morris ACL, (Emyr) Huws has been out for over a year, (Tom) Adeyemi over a year, Ben Folami’s Achilles is going to keep him out for seven/eight months...

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“It’s incredible, it really is. I don’t know why it’s like that.

“It’s a blow for Freddie, first and foremost. And for the football club it’s a huge, huge blow.”

German striker Quaner missed Sunday’s 3-0 defeat at Norwich City with a hamstring problem. Lambert explained: “Hopefully hew’s going to be okay. He trained this morning and if there’s no reaction to it he’ll be in the squad.”

Experienced centre-back James Collins has missed the last two games with a tight hamstring. Lambert explained: “He’s still feeling it a bit. It’s getting better. Maybe this one is just a little bit early for him.”

Captain Luke Chambers sat out the 1-0 home defeat to Sheffield Wednesday with a foot injury and then played through the pain against Norwich. He’s also playing with a broken wrist following a heavy fall during the home win against Rotherham on January 12.

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“We need to see how Luke Chambers is,” said Lambert. “If he could do it I’m pretty sure Luke would do it. He felt good on Saturday, he played, but towards the end his foot started to feel painful.

“It will be a call right at the death whether plays or not.”

Meanwhile, Lambert revealed that winger Gwion Edwards, whose last appearance was in the FA Cup defeat at Accrington Stanley, has also been an enforced absentee.

“He’s been injured with a frustrating groin problem,” said the Blues boss. “He trained this morning for the first time in a few weeks. He’ll be in the squad but it’s still a bit early for him.”