Mindful that the Belgium international has under a half year staying on his agreement, the Blues attempted, and failed, to make sure about the signature of the 32-year-old in January.
Regardless of that setback, Frank Lampard stays enthused about acquiring the attacker on a free transfer toward the end of the period.
Nonetheless, as indicated by Sky Sport Italia, Mertens is currently prone to extend his stay at Stadio San Paolo in the wake of having conversations with president Aurelio De Laurentiis.
The report guarantees that the player is required to consent to another two-year deal, which would take his spell at the Serie A side to nine years.
Since 2013, Mertens has contributed 119 goals from 302 appearances in all rivalries.