Playing mainly as a left winger, Koroma was a key part of the first half of Huddersfield's season, but picked up a hamstring injury against Sheffield Wednesday in December and has not appeared since.
“It's very positive to see him playing again,” said coach Carlos Corberan. “He was out injured for a long time but we know how important he was at the beginning of the season. What he showed on the pitch was very important.
“We can now consider him for the last part of the season, because it's clear if he didn't do the work he did at the beginning of the season then nobody would now be asking, 'Where's Josh Koroma?' but he had a very good impact .
“His recovery has been very professional and now has a chance to make some minutes. He'll travel with the team.”
Midfielder Vallejo picked up an injury which was later diagnosed as concussion early in the Easter draw at Brentford, although he carried on playing until midway through the first half.
Footballers have strict protocols to follow before they can return to training and when all is well, the process usually takes seven days but the Spaniard is still not available for selection.
“Alex Vallejo is still out with concussion,” confirmed Corberan. “We still don't have confirmation he is ready.
“Alex had some after-effects after concussion and his range of vision is restricted. He'll have a scan on Monday.
“It's a dangerous injury and we need to follow the medical advice.”
Yaya Sanogo is expected back from injury next week, whilst Alex Pritchard will also be sent for a scan on Monday having suffered a kick to one of his muscles in this week's B team game.
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