"One of my problems in this job is that I have good players and everyone has their story - Christian has a price-tag, Ross Barkley is an global player, so too is Mason Mount", Lampard said in his pre-match press conference.
The USA global was completely left out of the Chelsea squad for Wednesday night's Champions League win at Lille, and has not featured in the Premier League for the club since the 2-2 draw with Sheffield United on August 31.
"At the moment, he has really delivered and long may that continue, but I think there is a lot more to come still", Lampard added.
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"The progression was huge but the main thing I saw in him was work ethic", Lampard said of his season with Tomori at Pride Park. He's not just an incredible handful for defenders - he's running them, he's holding the ball up, he's controlling it, he's got good feet - he's also getting his goals, which is brilliant for him. I will just keep going, keep pushing. "You want to play, be on the field and be in the team as much as you can and it hurt not to be there, but I'm happy I got my opportunity today". I hear things, I see things, but I do my best to block it out. I will just keep going, keep pushing.
The 31-year-old was forced to adopt a more limited role in the Chelsea squad under Sarri but has now revived his career under the Blues boss, Frank Lampard this season. "From here all I can say is to encourage him to keep working because we know that a new country, a new team, a bit of time of adaptation", said Azpilicueta, after Pulisic was left out the squad for the Champions League tie against Lille on Wednesday.
"I know people will talk about the circumstances [of the transfer ban], but he also has Olivier Giroud, who's a World Cup victor, and also [Michy] Batshuayi who's a top-class Premier League striker in my opinion as well". "When I go there I definitely want to go in and get minutes and just gain more worldwide experience".