Isak was forced off in the first half of the Magpies' 3-1 win at Aston Villa at the end of January with a groin injury, and the striker subsequently missed last weekend's 4-4 home draw with Luton Town.
Gordon, meanwhile, was substituted at half time in that draw with the Hatters after sustaining an ankle injury, and the winger was later spotted leaving St James' Park on crutches.
Although an appearance at the City Ground this weekend will come too soon for the pair, Howe is hopeful that Gordon's injury is not a serious one, while he has also revealed that Isak is «making good progress» in his rehabilitation.
Speaking about both players at a press conference on Friday, Howe said: "[Gordon] hasn't trained this week. We don't think the injury is serious – we hope he is back sooner than later.
"[Isak] won't make this game. We hope he won't be too far away for the following games, but he doesn't have a fixed return date yet. He is making good progress – the injury isn't as serious as first feared."
Howe has also issued a fitness update on midfield duo Joe Willock and Elliot Anderson, who have spent lengthy periods on the sidelines with respective calf and back injuries.
«They're doing well at this moment in time,» said Howe. «Joe's working really hard – he's not trained with the group yet, but he's working really hard with the sport science team. He's in that final stage of his rehab and we hope he can be back pretty soon.»
«Elliot's not far away either. He's had good news on his scan a while ago and he's now really kicked up his running, so both players are
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