Boyd, 31, was 6-8 with a 3.52 ERA for the Expos. Texas sent minor-league pitchers Jonathan Hurst and Joey Eischen, plus a player to be named, to Montreal.
"I expected it, and I'm glad to be going to someone who wants me to pitch for them," said Boyd, who can become a free agent at the end of the season. "But I want to come back to the National League next year. I like it better here, and I think it's better for me."
Boyd is scheduled to start Wednesday night at home against the Boston Red Sox, the team he pitched for through the 1989 season.
"We owed it to our team and to our fans to make a move to strengthen our pitching staff," Rangers manager Bobby Valentine said. "It helps that he knows the parks [in the AL], but there are a lot of stars in the league who weren't stars when he was here.
* CUBS: Former Cy Young winner Rick Sutcliffe said Saturday that he is considering retirement after losing his third straight rehabilitation start in the minor leagues.
"Maybe it's time for me to do something else," Sutcliffe said. "I'm not making pitches to get anybody out."
Sutcliffe, 35, gave up 11 hits and six runs before being chased in the fifth inning of Class AAA Iowa's 7-2 loss to Buffalo.
He is scheduled to talk today with Cubs officials.
"I'm just tired of stinking the place up," Sutcliffe said. "I'm just tired of not seeing the improvement that I should be showing. I don't know who that guy was out there tonight."
Sutcliffe, sidelined by arm problems for two years, has lost all of his rehabilitation starts. He was beaten 10-2 last Monday by Buffalo and lost an earlier assignment in Class A.
Sutcliffe, the 1984 Cy Young winner with the Cubs, has a 9.00 ERA in 18 minor-league innings this season.
"I know he wanted to pitch well," Iowa Cubs manager Mick Kelleher said. "He's just struggling with his control."