The Sulphurites suffered their first defeat of the campaign when they went down 2-0 at Port Vale at the weekend, but it was not just their seven-game unbeaten record that was lost in Staffordshire. Influential midfielder Alex Pattison suffered a head injury within seconds of kick-off and had to be replaced, while left-back Lewis Page limped off before half-time having tweaked a hamstring. A disastrous opening period was then capped off deep in stoppage-time when on-loan Sunderland winger Jack Diamond was dismissed for a second bookable offence. Left-back Lewis Page is expected to miss the Sulphurites' next two matches. The latter’s one-match ban, concussion protocol and the fact that Page now needs to rest the affected muscle means that none of the trio will be available for selection down in Sussex. “Two injuries, one within the first 20 seconds, didn’t help us on Saturday," Town boss Simon Weaver reflected. “Two injuries to good players plus Jack’s sending off, that’s a third good player off the pitch. It really unsettled us, to be honest. “I’d imagine that Lewis Page will probably be back for a week on Saturday and I imagine it will be the same for Alex Pattison as well. Fortunately we haven’t got a game a week on Tuesday, so they just look like missing the two games. "Alex suffered some dizziness. Obviously his head had been taped up and I was worried about him. When he came to the side he looked a little bit dazed and he said he wasn't quite right. "With head injuries it is of paramount importance that you look after the player. As much as he's a big player and some people would be saying 'keep him on there', it's a serious business." All three men will be missed. Pattison, in particular, has been a revelation since joining from Wycombe Wanderers this summer adding drive and a genuine goal-threat to the Harrogate midfield, netting three crucial goals in his first two matches. Diamond, back for a second spell at the club, is near-unplayable on his day and, although he is yet to fully hit his stride, former West Ham defender Page provides balance on the left of Weaver’s back-four. Yet, as is always the case, the absence of one player affords another an opportunity, and it is likely that Simon Power, Ryan Fallowfield and Lloyd Kerry - all of whom came off the bench at Port Vale - will be handed starts against Crawley. Confirming that the latter will indeed take Pattison’s place in the engine room, Weaver added: “Lloyd Kerry always does well for us. "We are looking forward to him being in the starting XI and it’s a great opportunity for him. “He has his own unique ability, dropping on every second ball going and he knits it all together.” Town head to Crawley third in the table having won four and drawn two of their opening seven League Two fixtures. The Red Devils currently sit 14th, with 10 points to their name.