The 33-year old Scottish centre-back and 31-year old English right-back became teammates at St James' Park when the latter arrived from Everton's youth academy in 2002 and now find themselves suiting up for the 2014 MLS season with Toronto FC.
Orr spoke highly of Reds skipper Caldwell, who arrived at BMO Field from Birmingham City in May 2013, saying that he has enjoyed being back alongside his old mate in a completely different environment.
"I've loved it," Orr told MLSsoccer.com.
"Steven's my roommate so we've spent just over a month together and shared rooms in preseason. He's very, very important to the football club, he's vital as a leader and a character in and around the place, and he's certainly got a lot to offer on the field.
"It's quite funny actually, seeing that he hasn't changed one bit," Orr continued.
"He's still exactly the same. Very vocal, and his leadership qualities are all still there. It's a joy to play with Steven and I'm looking forward to forging another partnership with someone I call a friend."
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