Frank Lampard has praised Chelsea's "strong core" for the club's continued success.
The 34-year-old midfielder helped guide the Blues to Europa League glory last season before securing Champions League qualification.
"One thing that has helped us remain successful over such a long period is a strong core, a strong spine," Lampard told The Sun. "I mean that in terms of players - their ability, personality and the leaders. You need people like that in the dressing room."
Lampard became Chelsea's record goalscorer last season as he netted his 203rd goal in 12 years at the club.