The long-rumored deal between Boston and Montreal came to fruition on Tuesday when the Red Sox acquired Expos closer Ugueth Urbina in exchange for right-hander Tomo Ohka and left-handed pitching prospect Rich Rundles.

The Red Sox also will receive cash considerations from Montreal.

The deal finally came down just before Tuesday's 4 p.m. ET deadline after conversations between the Red Sox and Pittsburgh failed to produce an agreement that would have sent Pirates closer Mike Williams to Boston, a source within the Pirates' organization said. Pittsburgh ended up shipping Williams to Houston for Tony McKnight.

Urbina was 2-1 with a 4.24 ERA for the Expos this season, with 15 saves. He is coming off of major elbow surgery last year, and earlier this summer he failed a New York Yankees' physical examination, which would have sent him there.

"He's death to right-handed hitters," Red Sox general manager Dan Duquette said. "If you need a strikeout in a key situation, he can provide that."

Ohka was 2-5 for Boston with a 6.19 ERA this season. He was currently pitching for Triple-A Pawtucket, where he was 2-5 with a 5.57 ERA.

Rundles was 7-6 with a 2.43 ERA and Class A Augusta.

The Associated Press contributed to this report.