Paddy McLaughlin says Cliftonville will have to be "very careful" with Joe Gormley's hamstring injury.
The talismanic striker scored in the 2-1 defeat to Linfield but had to go off just after the hour mark.
McLaughlin said the 29-year-old had aggravated a hamstring injury but hopes it isn't a long-term problem.
One positive for the Cliftonville boss was the introduction of new signing Michael McCrudden who made his debut, and the return of Chris Curran from injury.
“Michael came on and did well,” McLaughlin told the club's website.
“It’s his first game in a few months because he’s in the off-season, coming up from the League of Ireland.
"Getting him on the pitch was great to see because he showed a few flashes of his quality and ability.
“It’s disappointing it was at the expense of Joe – he went off with a hamstring injury that he’d been carrying for a while. If it goes on him, he could be out long term, so we’ve got to be very careful with him.
“Hopefully it’s not too bad but it’s good to see that we’ve got the quality of Michael McCrudden coming onto the pitch, hopefully with a few games and sessions under his belt he’ll be up to speed in no time."
McLaughlin admits the busy festive season took its toll on some of his players, forcing the manager's hand into bringing Curran back into his squad earlier than expected.
Influential defender Jamie Harney was also an unused substitute in Monday's game.
“There were quite a few carrying knocks and niggles from the festive period. It’s so intense and there were so many games," he added.
“Chris Curran, realistically, probably should have sat the game out. Joe Gormley probably should have sat the game out but hopefully they aren’t too bad.
"Hopefully Chris is over his problem and Jamie (Harney) will be back soon.”
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