The Colombia international completed a season-long loan move to the reigning Premier League champions from Ligue 1 side Monaco on Friday afternoon.
Falcao scored just four goals in 29 games for Manchester United during his loan spell at Old Trafford last term.
Former Tottenham Hotspur striker Lineker doesn’t expect Falcao to push Costa or Remy for a starting spot in Jose Mourinho’s side.
Chelsea signing Falcao on loan is interesting. Mourinho clearly using him for cover, he'll certainly be behind Costa, possibly even Remy.
— Gary Lineker (@GaryLineker) July 3, 2015
The Colombia international returned to the Ligue 1 side after a disappointing loan spell at Manchester United last season.
Falcao will link up with his former Atletico Madrid team-mates Thibaut Courtois and Filipe Luis at Stamford Bridge.
The 29-year-old will also join his compatriot Juan Cuadrado, who moved to the west London side from Fiorentina in January.
Falcao, who missed the start of the season due to a string of fitness problems, started jut 12 top-flight games under United manager Louis van Gaal.
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