Lampard scored again in their FA Cup win over Brentford on Sunday.
"I understand why the fans want [Frank] here, the supporters love him. He is a great guy, a great captain who is a legend, and still playing, so for me and the team-mates it is an honour to play with him. He scored already 13 or 14 goals this season, and for 10 years he has been scoring more than 10 in the Premier League. He is one of the best," Mata told chelseafc.com.