West Ham enjoyed a fine start to the campaign, establishing themselves in the upper reaches of the table with victories over the likes of Liverpool and Manchester City.
However, a winless run of two draws and a defeat last time out at Everton has followed their 2-1 win against the champions last month.
Allardyce remains satisfied with the level of his team's performances, but is wary of repeating previous struggles in the period leading up to Christmas and undermining the impressive progress made at Upton Park this term.
"It's a hugely important time for us. Historically we've struggled at this point," he said.
"The last international break was, in many ways, the worst I've suffered because three players came back injured. Dealing with the amount of games in such a short period of time is a massive test for us all. It'll define how our season goes, I think.
"We haven't achieved the results that our performances have merited, which is really disappointing.
"We have to turn this slight blip around quickly. Winning games gives you the confidence you need and we haven't had that recently."
Stewart Downing was one of the players to report back with an injury earlier in the month as a knee problem sustained on his England return ruled him out of the trip to Goodison Park.
Downing has returned to training alongside Cheikhou Kouyate (knee), while fellow midfielder Mark Noble is a doubt having sustained a knock against Everton.
Leading scorer Diafra Sahko (back) is likely to miss out again and defender Winston Reid is suspended.
As West Ham look to rekindle the magic of their earlier hot streak, the challenge for Newcastle is to maintain a fantastic run of six consecutive wins in all competitions that leaves them lying fifth - a place above their weekend opponents.
A defence that has been breached only once during that winning period could be boosted by the return of Fabricio Coloccini (calf) and Steven Taylor (knee).
Midfielder Cheick Tiote is also back in training with a buoyant squad following a calf problem.
"It's a big week in the Premier League - three Premier League games in seven days - so it's an important spell to have all your players around," manager Alan Pardew said.
"It is [a boost] because we've had a terrible run of injuries and kept the winning run going so it's testament to the squad - the players have been phenomenal in this spell, and even on the training ground this week it's really difficult to calm them down.
"They're really on fire, they're enjoying their football and you can see it, so we should be in a good place for Saturday."
Ryan Taylor will miss out for Newcastle, although his knee problem will only sideline him for three to four weeks and is not a recurrence of the midfielder's cruciate ligament problems as first feared.
