New Town signing Tom Lockyer will have to bide his time for a place in the side according to boss Nathan Jones.
The 25-year-old was signed at the start of the month from Charlton Athletic, after the Addicks were relegated from the Championship last term.
He missed a week of training with his new team-mates due top international duty, winning his 11th and 12th caps for Wales in their Nations League matches with Finland and Bulgaria.
Although he was tipped to make his Town debut at Oakwell on Saturday, Lockyer was seen taking part in some pre-game warm-ups with head of coaching and player development Adrian Forbes, before taking his place in the stands, not included on the bench by Jones.
On why that was, the Hatters chief said: “He’s played two games and we went with the same side that won last week, so I think that was justified.
“We’ve brought him but we’re not just going to all of a sudden change everything we do.
“We’ve got Matty Pearson who’s been a warrior for us, we've got Sonny Bradley who's been fantastic, now we’ve got that real, real competition.
“I could have put him on the bench but with Glen Rea playing and (Martin) Cranie playing, we’ve got plenty of cover on pitch for centre halves.
“So I was able to add another attacking options on the bench and that’s just picking a squad.”
One of Luton's other summer signings did make his league debut for the club, on-loan Rhys Norrington-Davies starting at full back as Town kept their first clean sheet of the campaign.
When asked to describe the Welsh U21s display, Jones added: “Outstanding, absolutely outstanding, a front footed left back, everything I thought he would be, he was today.
“There’ll be more to come from him as that was his debut, and yes, we want more from him.
"But as far as debut goes, and from what I’ve seen, that’s what we had today, so superb, really, really pleased.”