The Premier League's form team West Ham United meet the division's biggest strugglers Aston Villa at Upton Park on Saturday. Only league leaders Chelsea can match West Ham's haul of 10 points over the last four games, with the Hammers (5-2-3) tasting defeat just once in the last seven matches in a run that has vaulted them to fifth in the table. In complete contrast, Aston Villa (3-1-6) have the worst form in the Premier League, with six consecutive defeats and just a single goal scored in that run, leaving them only one point off the relegation zone after picking up 10 points from their first four games. "There's a huge pressure that comes upon you when you lose so many games on the trot," West Ham boss Sam Allardyce said about his opposite number Paul Lambert. "He (Lambert) must be wondering what he's doing wrong at the moment, because I watched the game against Tottenham last Sunday and thought how unlucky he was that he lost that game one to a sending off, and two to a deflected free-kick. That seems to happen when things aren't going for you. "We have to make sure we try and continue their poor run. I imagine it'll be a very difficult game in terms of trying to break them down and we'll have to be really aware of not leaving too many spaces to let them play that good counter-attacking game that they seem to adapt to well away from home." Lambert's Villa have conceded 15 goals during their swoon - letting in at least two in each of those games - and will be without Christian Benteke after the striker was shown a straight red card in last Sunday's 2-1 loss to Tottenham Hotspur. "Footballers never enjoy losing games, but that Tottenham defeat really hurt," Villa midfielder Tom Cleverley said. "We all felt we should have taken something from the game. But it's definitely a performance we can build on. We did a lot of things right in the game. "I thought when the red card incident happened that if we can win this game now it can really kick our season off. Unfortunately it wasn't the way it turned out. But that's even more reason to pull together, work even harder in training and get a result against West Ham." Villa are without Alan Hutton (ankle), Libor Kozak (broken leg) and Fabian Delph (shoulder) through injury. West Ham were boosted by Andy Carroll's return to training in the week following a lengthy absence with an ankle injury, while Winston Reid (hip) and Diafra Sakho (shoulder) are also close to comebacks. However, Allardyce will remain without the services of Guy Demel (hip). The Hammers took four points off Villa last season and didn't concede a goal in either match. However, those results were an exception rather than the rule in this fixture, with West Ham winning just three of their last 14 Premier League meetings with the Villans.