Left-back Brandon Ormonde-Ottewill is training with Barnsley as they explore the free agent market.
The 26-year-old came through the Arsenal academy then spent two years at Swindon before playing in the Dutch second division at various clubs for five years.
He left Excelsior in the summer and has been at Oakwell today.
The Reds brought in right-back Tom Edwards, on loan, and central midfielder Adam Phillips, on a three-year deal, on deadline day last Thursday but missed out on two other deals that were very close.
They are understood to have been trying to strengthen up front and at left wing-back.
They can still sign players who do not currently have clubs.
After the 2-0 win at Sheffield Wednesday on Saturday, head coach Michael Duff said: “We will see if there’s anything out there. We’re always looking to improve. If not, we focus on the next window.”
Meanwhile, National League South club Havant and Waterlooville have announced they have signed young Reds winger Tomas Kalinauskas on loan. The Chronicle understands the deal is not fully official yet but is expected to go through.
The Lithuania under 21s international has not made an appearance yet for the Reds, whom he joined at the start of the season before being loaned to AFC Wimbledon for two League One games then released in the summer but re-signed.
Barnsley are expected to send some of their development players out on loan to non-league clubs, but there is no rush as the National League has no transfer deadline until March. The likes of Jasper Moon, Jason Sraha and Joe Ackroyd have not played in the league this season.
Barnsley are also willing to move on striker Aaron Leya Iseka who is not part of Duff’s plans. The 24-year-old Belgian, who has not played in the league this season, did not leave during the English window but clubs in a few other European nations can still sign players this week. The Chronicle understands there is no move currently imminent.