Jack Shepherd has joined Barnsley's fellow League One club Cheltenham Town on loan until the end of the season.
The 22-year-old signed from eighth-tier Pontefract Collieries last summer and has made six League One starts, including the last four.
He is the second centre-back to leave Oakwell for a relegation-battler in the third tier today after Kacper Lopata moved to Port Vale.
Interim director of football Bobby Hassell said: “We have been extremely impressed with the attitude and application of Jack since his arrival back in the summer.
“He has made massive strides to come from Step 7 of English football to performing in League One and has surpassed all of our expectations.
“This move allows Jack to continue his development at the same level as Barnsley, furthermore, I have a good relationship with Darrell (Clarke) so am confident that a good environment will be created for Jack to improve.”