Spencer backs Chivas USA keeper Guzan for Celtic success
"Brad is the money," Spencer told the Daily Mail. "He would have no problem playing in the SPL right now.
"He throws himself about, he's really brave and he already has some good international experience. He played really well in a game against Sweden last weekend and that clean sheet raised his profile further.
"No disrespect, but if you are performing well on the international stage, then I'm pretty sure you can handle playing in Scotland. Obviously, Celtic have Boruc in there and the question would be whether Brad could get enough game time to continue developing if he was to sign.
"But he definitely has the ability to go on and star at that level."