Chris Wilder says the desire and hunger shown by James Wilson were key factors to why the defender has been signed.
The 27-year-old joined the Blades on a two-year deal on Tuesday, having rejected a new deal at League One rivals Oldham Athletic and Wilson was more than willing to be put on trial by the Blades prior to signing on the dotted line, something that impressed the Gaffer.
Wilder commented: "James has shown the desire to come here. He could easily have gone 'I'm not having that, I've played my games, I'll go to someone who will take me now' but that's not what he did.
"I like the fact we've signed someone who is hungry to play for us. And, above all else, that's exactly what we want.
"You don't get international recognition if you not a good player. He knows what it takes to go to places which I won't name but aren't the most comfortable or fashionable.
"I spoke to people who have worked with him, who I trust implicitly, and who said there's a player there.
"James has been in with us for a week and we've had a good look at him."
The Blades boss added: "Our recruitment has to be right. I'm not just going to go out and get household names.
"I want players who will make us better with the way they play, their attitude and their desire. He will now battle it out with the other defenders for a shirt."