Reports emerged over the weekend linking Morgan Fox with a summer move to Birmingham.
Swansea and Manchester United were also mentioned as possible destinations for him.
Fox has made more Championship appearances than any other Charlton player this season, making the left-back berth his own.
When Rhoys Wiggins regained fitness at the end of last season, he was unable to displace Fox, and was transferred to Sheffield Wednesday before the start of the season.
Fox has previously been linked with Ipswich. He has two years remaining on his Valley contract and seems in no hurry to leave the Addicks.
Jason Euell’s Under-21 side were beaten 2-1 in their play-off semi-final against Sheffield United at The Valley on Monday afternoon.
Skipper, Terrell Thomas, gave the Addicks the lead after 34 minutes, but was later to turn villain.
A bizarre penalty decision gave Diego Degirolamo the opportunity to bring the Blades level from the spot.
The game went into extra-time, and midway through the first period, the Blades’ striker took advantage of Thomas’ underhit backpass to notch his second.
Right at the death, Thomas received a red card as both sets of players clashed.
Charlton: Mitov; Staunton, Konsa, Thomas, Edwards; Dijksteel (Ahearne-Grant 103), Charles-Cook, Aribo; Kennedy (Lapslie 79), Umerah (Ansah 110), Hanlan.
Subs (not used): Beeney, Barnes.
Goal: Thomas 34.
Booked: Umerah 52 (diving), Kennedy 63 (foul).
Sent off: Thomas 120 (violent conduct).
Sheffield United: Eastwood; Cummings, Kelly, McGahey, Kennedy; Semple, Gilmour, Reed, Smith (Hall 82); Degirolamo, Brooks.
Subs (not used): Ramsdale, Charlesworth, Brown, Hallam.
Goals: Degirolamo 61, 97.
Booked: Degirolamo 44 (foul), Reed 120 (foul).
Attn: 307.
Jordan Cousins retained his Player Of The Year trophy, picking up the award for a second time at The Valley on Sunday evening. Alou Diarra – who won the CADSA POTY trophy – came second, with Johann Berg Gudmundsson finishing third.
Ademola Lookman was voted Young Player Of The Year by Valley Gold members, and Jean Huelin was honoured with the Colin Cameron Trophy, awarded to the outstanding fan of the year.