The Blues and The Hammers meet for the first time since August when the Chelsea cruised to a 5-1 victory at the London Stadium.
Chelsea have won five of their six matches in all competitions under Rosenior and could jump into the top 4 depending on results if they pick up 3 points against relegation candidates West Ham.
Palmer is happy to be at Chelsea
Rosenior first spoke on Cole Palmer, his fitness and his happiness as reports link with a move back to Manchester.
"He came through with two assists and an outstanding performance. He is absolutely fine. It's what be wants and I want (for him to be able to play 90 minutes).
"He is available to start tomorrow so I am really happy about that. When a player like that is at their top level they are at a top level. He is always happy."
Colwill returns
He was next asked about Levi Colwill's fitness concerns as he continues to recover from a long-term knee injury. Rosenior revealed that they have been in contact and he is ready to return.
"I spoke to him this morning. He's really good. What a professional. He's working so hard. It's been brilliant to see him back on the pitch running. He's itching to get back. But we need to make sure he feels 100% perfect when he's back."
Could he return this season: "Yes, but it's step by step. I don't want to make promises I can't keep."
Rosenior started his Premier League campaign with a 2-0 home success over Brentford followed by a 3-1 win at Crystal Palace last weekend. He will be aiming for another victory this weekend in what looks to be a great appointment so far as the former Hull City boss gets to grip with the English top flight.