Wrexham's dreams of a historic rise to the Premier League have been hit with a major setback following the news that star striker Kieffer Moore is set for a spell on the sidelines. The Wales international, who is the Red Dragons' leading marksman with 13 goals this term, sustained a hamstring injury during the thrilling 4-2 FA Cup fifth-round defeat to Chelsea. The 33-year-old missed Tuesday's defeat to Hull City and is expected to sit out at least another three crucial Championship fixtures, leaving a significant void in Phil Parkinson's attacking arsenal.The timing could hardly be worse for the Ryan Reynolds and Rob Mac-owned outfit, who currently sit sixth in the second tier. Any slip-up now could prove costly, though future campaigns will be aided by a major Championship rule change that expands the play-off format. For now, Wrexham must navigate the traditional four-team lottery without their primary goal threat as they prepare for a high-stakes Welsh derby against Swansea City on Friday night.Parkinson has been hesitant to put a specific date on Moore's return, especially with the international break looming. "I'd like to not say officially what it's going to be because Kieffer needs to see how it settles down the next few days," the boss explained. When pressed on whether the forward would be available for Wales’ World Cup qualifying play-off against Bosnia and Herzegovina, Parkinson admitted: "I think we'll know more in a week or two on that but I'd say he's a doubt for that, a big doubt."Detailing the nature of the setback, Parkinson revealed that a scan showed a more complicated issue than initially feared. He added: "Kieffer played Saturday and did well when he came on. After the game, there was a bit of tightness there and we thought he was okay, he trained Monday. We sent him for a scan and there's a split in the tendon. It's not the muscle, but it's the tendon and they're always contentious injuries because there's no definitive time scale on them."The bad news continues to pile up at the Racecourse Ground as wing-back Liberato Cacace has suffered a frustrating setback in his own recovery. The former Empoli man has endured a stop-start beginning to his career in Wales and has already missed the last seven outings for the club. With the promotion race heating up, losing another experienced head in the defensive unit represents a significant hurdle for the Red Dragons to overcome in the coming weeks.Add GOAL.com as a preferred source on Google to see more of our reportingWrexham's engine room is also feeling the pinch, with several key midfielders unavailable for the upcoming fixtures. Ben Sheaf has been ruled out for the remainder of the season with a medial ligament injury, while veteran Matty James continues to recover from a broken toe. To make matters worse, George Dobson is currently serving a suspension, leaving the technical staff with a selection headache ahead of the Swansea clash. Despite the mounting list of absentees, Parkinson remains defiant that his squad can maintain their pursuit of a Premier League spot. "Of course it's a blow but we've had loads of those moments and things since I've been here and we find a way, and that's what we're going to do on Friday," he concluded.