Harry Lennon has extended his Charlton contract until 2019.
In February, News Shopper revealed Lennon had a one-year clause in his deal, which the club could trigger.
The Charlton defender, 23, played 12 times last season after recovering from a serious groin injury.
He failed to play a single minute of football in Lee Bowyer’s 12 games in charge as the Addicks lost to Shrewsbury in the play-off semi-finals.
Lennon has made 40 Charlton appearances since making his first-team breakthrough in 2013.
The Addicks academy graduate faces a fight for a regular starting place next season with Jason Pearce, Patrick Bauer, Ezri Konsa and Naby Sarr ahead of him in the pecking order.
Charlton will announce their released and retained list on Friday.
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