Robbie Neilson praised Andy Halliday's versatility and "top-quality attitude" after the 30-year-old signed a new contract with Hearts until 2024.
The former Rangers player's deal was due to expire in the summer, but the Tynecastle club value his experience and his ability to play to a high level in various different positions and have moved to hand him a two-year extension.
"I'm really pleased to get Andy tied down," said manager Neilson. "He's more of a utility player for us but he's a very, very good one. It's difficult to get guys of that calibre who can cover in so many positions.
"On Saturday (against St Mirren), he came on at right-back for us but he can cover left-back, centre-mid, left-centre-half, left-mid. He also brings a depth of experience from having played at the top level.
"It's not just his performances on the pitch, it's also what he's like on the training ground and round about the place. His attitude is top quality.
"We have to build a squad here with continuity within the group. We have to keep players here for a number of years that we can then build players round about.
"I see Andy as one of those players, along with guys like Michael Smith, Stephen Kingsley, Craig Halkett and Craig Gordon, who have also extended their contracts recently. These guys will be key members of the squad going forward."
Neilson is yet to make a call on whether to offer Austrian midfielder Peter Haring a new contract.
"Peter's one we've still to make a decision on," he said. "We always want to progress the club and bring new players in, so he's one who's in that wee group that we're still not 100 per cent sure on."
Neilson is hoping Hearts attacker Barrie McKay can force his way into the Scotland squad for the upcoming World Cup play-offs.
"I think Barrie's an exceptional player who should be round about the Scotland squad," said the Tynecastle boss.
"Steve (Clarke) makes the decision on it and there are a number of top-level players in that position but Barrie and Craig Gordon have probably been the two main performers for us this season.
"When we brought him in, we spoke about what his objectives would be and it would be to help Hearts get as close to the top of the league as possible and win cups but also to try and get into the national team, and hopefully he's getting closer."
