West Ham striker Andy Carroll says manager Sam Allardyce is a grandmaster ready to tactically outclass Chelsea boss Jose Mourinho on Boxing Day.
Allardyce believes January's goalless draw at Stamford Bridge -- when Mourinho accused the Hammers of playing "football from the 19th century'' -- was the turning point last season.
Since West Ham have improved markedly to sit in fourth place at Christmas, their highest December 25 position in almost 30 years, ahead of Friday's game at Chelsea.
"We can do anything," Carroll said. "He knows just as much as us how to beat managers, their tactics.
"He knows what they are going to do against us. It's just a game of chess, really, looking a move ahead.
"He's not the same every week. He wants a win, but you've got to watch the teams, how they're playing, how we're going to break them down and win the game."
The Hammers have one defeat in 11 games and Carroll attributes the transformation to Allardyce and changes in personnel.
"He's brought in some great players," added Carroll, who has scored three times on his return from injury.
"He's changed the team around a lot and the players he's brought in have settled in nicely.
"All the lads are buzzing about at the minute, and it comes from that really, the manager's choice of players and how he wants to play now.
"We're playing great football, and I think any team that we play against is going to be worried about us.
"We've got more than one attacking option: play it on the floor, play it in the air, down the sides.
"There's a belief. Everyone's flying at the minute. Everyone's looking forward to every game.
"Every week we're thinking, oh there's another three points, potentially."