Chelsea are believed to be watching a pair of promising young English defenders.
The West London club are making plans to cover 35-year-old club captain Terry who could quite possibly finish up at the end of the current Premier League season.
It is understood that Chelsea are determined to lure a player in the same mould as the great 'JT' and have commenced an exhaustive scouting mission to find that player in particular.
The Blues are eager to comply with the Premier League's homegrown player rules which has seen them show significant interest in both Keane and Gibson, who are key performers at their current clubs.
23-year-old Manchester United youth product Keane has been with the Clarets since 2014, racking up 72 first-team appearances, following temporary spells at Leicester City, Derby County and Blackburn Rovers.
Gibson, also 23, has been with boyhood club Boro since he was 12, playing 116 times, after enjoying with loan stints at Plymouth Argyle, York City and Tranmere Rovers.