Rein was a key member of Penrith's premiership-winning Intrust Super Premiership team under Brennan last season and has been lured to join him at the Titans.

"I came here not knowing many of the guys but they've been very welcoming and I can't wait to rip in for the rest of the pre-season," Rein said on Monday.

"I'm looking forward to the challenge and having the opportunity to link up with Garth again is great. He is a champion guy and a great coach.

"Once he gave me a call it was a pretty easy decision."

Rein, a Kiama Knights junior, arrives at the Titans after one season at the Panthers, where he made five NRL appearances after his exit from St George Illawarra.

He had played 132 games in six seasons at the Dragons before his career seemingly stalled, but will now look for a fresh beginning at the Titans.

Rein is likely to join Karl Lawton in backing up first-choice rake Nathan Peats next year.

"Mitch is the ultimate competitor and someone that I enjoy coaching," Brennan said.

"He is a terrific trainer and his attitude across every aspect of the game can't be faulted.

"He has made a smooth transition into the club and I know he is looking forward to working hard over the next few months of pre-season training.

"It's great that we have been able to acquire an experienced player who has played over 130 NRL games and represented Country Origin."