The pair have been spending time on trial Ewood Park as they seek new employment for the 2014/15 campaign.
Goalkeeper Jamie Ashdown has also been working with Blackburn, but he is another now exploring other options.
Bowyer is delighted to still have Spence within his ranks, with the former West Ham United trainee offering enough to suggest that a permanent deal may be beneficial to all concerned.
“Jordan Spence is still here, Carlos was just training with us and now he’s not training with us, while Jamie Ashdown was subject to an offer from another club and I think he’s gone to try and sort that out,” Bowyer said in the Lancashire Telegraph.
“We’re not blessed with many defenders and it’s been a good opportunity for us to have a look at Jordan.
“He’s been up all week and we need to see him in another game. Hopefully we can get that sorted and take it from there.”
Bowyer added on his plans for the remainder of the transfer window: “We could do with some numbers because the ones in the squad at this moment in time, the likes of Yann Songo’o and Jack O’Connell, haven’t got Championship experience, although they’ve got potential, that’s for sure.
“So we just feel we could do with some experienced ones with Championship knowledge.
“But I fully understand the position of the club with Financial Fair Play. It’ll be a case of sitting down with the board and the owners and seeing how we can be competitive.
“If we have to go with what we’ve got, that’s what we’ll do, and with the quality that’s in the squad now, I’d be happy with that.”