Sam Allardyce has credited Saturday's sensational 3-1 win at home to Chelsea to his players' heart, desire and tactical awareness.

The Hammers were trailing by a goal at half time but regrouped at the break to hit back with a three unanswered strikes in the final 30 minutes. Although the half-time introductions of Momo Diame and Matt Taylor were crucial, Big Sam put the comeback down to his team following the clear tactical plan he had devised.

"It's very rewarding as a manager to see your players turn a game around for you," Big Sam said. "It shows that you've got to be able to change your tactics at any stage of a Premier League game. One of my thoughts whenever I approach a game is that you might have to be adaptable whenever you play.

"I think we changed the tactics at half time and they applied those tactics to the letter and started to expose Chelsea's weaknesses, which was their defence and in behind the full-backs. Matt Jarvis and Matt Taylor started getting in and then we started playing off Carlton Cole and he started to affect the game with his abilities. It paid off and we scored three great goals.

"We changed the players as we overcomplicated it a bit in the first half instead of keeping it simple. I said to them at half time that Carlton Cole, when you play it to him, is having a very good game. He's causing their central defenders problems and then we can break off the midfield and get people like Momo Diame in the game.

"The way the lads applied themselves is all about the desire and belief and the quality to do so. All of those three things upped to a massive level in the second half. I think we almost started from the first whistle and continued it all the way through. They've cracked in the end and we've deservedly won 3-1."

The win capped off a tough six days for West Ham United, which saw them play fixtures against three of last season's Barclays Premier League top four. After not picking up a point in either of the first two games with Tottenham Hotspur and Manchester United, Allardyce was certain his players' confidence had not been affected and he was proved right as their character saw them dominate the European champions after the interval.

"To play one of our big rivals and to see the end of a tough six days and finish in that style is one of those outstanding moments of the season. Being able to turn it around at half time was great as it looked like we might find it hard to get back into the game.

"It was a fantastic game as our defending had to be desperate and our goalkeeper had to pull off some outstanding saves, which is always needed when you play a team of Chelsea's size, but in the end it's been an outstanding victory for us at the end of a very difficult six days."

Cole carried on where he left off following his impressive cameo against Manchester United last week and terrorised the Chelsea defence throughout. He grabbed a deserved equaliser with a header before Modibo Maiga continued his knack of scoring in front of the Bobby Moore stand by capping off a fine move at the death. Both players are likely to see more game time in the near future with Andy Carroll now ruled out with a knee injury.

"Carlton Cole's performance certainly softens the blow of losing Andy Carroll but of course it's a huge boost for Modibo Maiga too. We need him more than ever now. Him and Carlton are going to be major players for us. We've now stayed in the top half of the table for the first half of the season and we've never been out of the top half and that shows what desire the players have.

"The substitutions were a big decision and we've got to remember Matt Taylor's contribution as well as Mo Diame and Modibo Maiga scoring. It ended up being a great day to be a West Ham fan and a great day for everyone associated with the club."

Big Sam will be hoping both strikers can continue their form after it was confirmed Carroll could miss six or seven weeks with a knee injury.

"Andy Carroll has a ligament injury and his knee is in a brace. Liverpool have sent a medical representative when he went to see the specialist. He has given the advice about what to do and the hopefully he'll recover as quickly as the specialist suggests."