The 20-year-old officially signed for Chelsea FC in the January transfer window but he was immediately loaned back to Borussia Dortmund for the remainder of last season.
Pulisic is now preparing to link up with his new Chelsea FC team-mates and get to work under new boss Lampard as the west London side eye a successful season under their former midfielder.
The USA international was in action for his country at the Gold Cup immediately after the end of the Bundesliga season.
He is currently still on his holidays but Pulisic has chosen to link up with the Chelsea FC squad in time to join them for their pre-season tour of Japan.
Speaking in an interview quoted by Metro, Lampard said: “Christian joins us on Tuesday.
“He’s had a short break, but he wanted to get back with us quickly, which I certainly appreciate. I appreciate that [coming to pre-season early after the Gold Cup], it’s how I would have been.
“It’s a big move for him to a huge club. He’s a top young player. He’s only going to go one way in terms of his career – he’s going to go up and be a big signing for Chelsea. I hope so. I look forward to working with him.
“It’s important we start the season as well as we can. I know we have injuries, people back at Cobham now that are influential players for us at similar positions, so we’ll need him.”
Pulisic scored four goals and made four assists in 20 Bundesliga games for Dortmund last season.
Chelsea FC will be looking to at least maintain their place in the top four next season after they finished third and won the Europa League under Maurizio Sarri last term.
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