Chelseahave secured their progress to the last-16 of the ****UEFAChampions League and that is a significant achievement for Liam Rosenior and his side.
They will be hoping to qualify for the competition again for next season and recent results have put them in a promising position to do that.
After a run of disappointing results over Christmas, it still came as a surprise to many that Enzo Maresca was sacked, but Rosenior has come in and there have been positives from his appointment. In all competitions, they have only lost once under their new boss, and that was the first leg of the **EFL Cup**semi-final to Arsenal.
Last time out in the Premier League, they beat a struggling Crystal Palace 3-1 at Stamford Bridge. It was a comfortable win and **Estevao**put in an impressive performance for the Blues.
They will come into this game high on confidence.
However, West Ham have demonstrated an improvement in recent weeks. Nuno Espirito Santo's side have won their last two league matches with victories against Tottenham Hotspur and **Sunderland.**The Hammers still remain in real danger of relegation but they have a bit more belief now that they can close the gap.
However, on a weekend when Nottingham Forest play Crystal Palace on Sunday, West Ham play first and know that they will need a win at Chelsea to keep the pressure on Forest. Therefore, it may be a tougher game than Chelsea would have expected a couple of weeks ago.
When the sides met back at the London Stadium in August, it ended in a 5-1 victory to Chelsea. The Blues will know not to underestimate their opponents this time around.
It will be a test for Rosenior's side as they face a side who have found a new form of confidence. However, if they can get an early goal then they will likely still feel as though they can make it a difficult evening for the Hammers.
Chelsea will likely be wary of the form of Manchester United as Michael Carrick's side have won their last two matches to climb to fourth. They are currently a point above Rosenior's side but appear to have good momentum.
The London club will be looking for a win that would temporarily move them to fourth, ahead of United playing on Sunday and Liverpool not playing until later in the evening.
Come the end of the season, it is likely that fifth place will secure Champions League football as well, but the battle could remain tight. Liverpool, United and **Chelsea**are all currently level on ten wins and just two points separating the sides.
How will Chelsea approach the match?
Liam Rosenior has praised the depth of his squad on numerous occasions since arriving at the club and he may again use that depth this weekend.
After the European game in the week and an **EFL Cup**semi final second leg coming up next week, it may feel like a good time to freshen up the side.
They are competing on multiple fronts and Chelsea have the players to do it so it could be expected that some changes may be made, either to the starting line-up or during the game, with the cup fixture in mind.
The league is likely the priority, but they have a tough game at Arsenal where they need to overturn a goal deficit, if they wish to compete for silverware in the final.
So far, Liam Rosenior has done little wrong and is likely proving some of the outsiders, who doubted his qualities to lead a club like Chelsea, wrong. His side have looked solid and have scored regularly.
They will be expected to win against West Ham, so the challenge will be to live up to those expectations and get another positive result against a side from London.
With wins against Brentford, Crystal Palace and Charlton Athletic, as well as the matches against Arsenal, Rosenior has spent much of his time in charge currently facing sides from the capital. Victory would make it three consecutive league wins.