Newcastle have been dealt yet another injury blow after Joelinton was ruled out for at least six weeks with a thigh injury.
The Brazilian was forced off early in the second half during last weekend's 3-0 win at Sunderland in the FA Cup third round.
And a scan has now revealed the midfielder will be missing for an extended period, taking Newcastle's list of absentees back into double figures.
'The prospects over the next couple of weeks aren't good,' said Howe. 'It's an injury that will see him certainly miss, probably, a minimum of six weeks.
'It's a real blow for us because he's such an important player. He's had a very stop-start season unfortunately this year, where he was so consistent last year. He's had a few different problems and this is a big blow.'
Howe had hoped to welcome back the likes of Harvey Barnes (foot), Joe Willock (achilles) and Elliot Anderson (back) before the end of the month, but that now appears unlikely.
'Harvey is getting closer,' said the head coach. 'He hasn't trained with the group but he's been running on the grass, had his boots back on and kicking balls around. We're pleased with his progress currently but he still has a long way to go.'
On Anderson and Willock, he added: 'They're not expected back any time soon. Elliot is continuing his rehab from a stress fracture in his back. It's been a difficult injury to manage for him and he's not been very active for a long period of time, he's trying to let his back heal. I think he has another scan next week so hopefully that'll give us good news and he can start to build up his work.
'With Joe Willock, he's improving. He's building up strength in his achilles and feeling better, but still not running.'
Callum Wilson is still recovering from a calf
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