Cambridge manager Mark Bonner has made midfielder Paul Digby his second summer signing on a one-year deal.
The 25-year-old Barnsley product spent last season with Stevenage, and has further League Two experience with Mansfield and Forest Green.
"Once I spoke to the manager, he was confident about the way he wanted to play and his vision for the club," Digby said on the club's website. "His fresh ideas attracted me to Cambridge straight away.
"I like to play aggressively and win my battles in the centre of the pitch as well as get on the ball and help the team play.
"I know the league well now, I've been in League Two for the last three seasons but you're always learning."
Bonner added: "He is a leader, talks well and has an infectious personality. I'm looking forward to working with Paul and helping him find his best levels. He will fit in well and add more character to our dressing room."