Beckford put Huddersfield ahead in the 11th minute with a calm finish past Addicks keeper David Button to net his 16th goal in 19 appearances for four different clubs in the famous cup competition and delighting first-team coach Ian Miller.
"Jermaine can score goals. He's a natural goalscorer. I knew him from his time at Leeds and when he's smiling and happy, he's a threat," Miller said.
"Lately, he's just not had enough games due to injuries. But if you can get him and (Norwich City loanee) James Vaughan on the pitch they are a potent threat. The best in the Championship? I don't know.
"There's lots of teams spending mega money but they will certainly do for Huddersfield. They will both score goals."