Chris Wilder has claimed John Egan is worth double the £4m Sheffield United paid Brentford to sign him four months ago.
The Republic of Ireland centre-half is expected to make his 19th appearance for United against his former club tomorrow night.
Despite becoming Bramall Lane's most expensive ever signing when he moved to South Yorkshire in July, Wilder insisted: "John was their stand out performer and captain. If you look at what's being paid and where John's performances are now, it (the fee) is outstanding (value). It fully justifies us paying that fee for him. I think he's worth double what we paid.
"Hopefully, he's here for a long time. One hundred per cent, when you see what's being spent in the Championship and on players going into the Premier League, I definitely think it was a more than decent deal."
Egan, aged 26, spent two years in west London before joining Wilder's squad and has since emerged as one of the most influential members of a squad which travelled to Griffin Park earlier today ranked fifth in the table.
"I'd like to be in a position to make more of those signings," Wilder continued. Rather than just short-term players, it's important to have a structure and people who are going to grow with us."
Egan's compatriot Enda Stevens is also expected to feature against Brentford. With Mick McCarthy taking charge of Ireland for a second time over the weekend, Wilder believes the two men are destined for bright futures at both domestic and international level.
"I don't know if there's going to be a new dawn with a new manager going in, but I'd be very surprised if John wasn't a part of that going forward," Wilder said. "I should imagine Enda and John will be at the forefront of that. I'd be very surprised if John wasn't."
"John, for Mick, ticks all the boxes," Wilder added. "But you want what he brings, for any manager. He's fully committed, he wants to win, he's technical and wants to defend properly."