Teemu Selanne is an unrestricted free agent, too, but no one expects the 43-year-old Finnish Flash to leave the Anaheim Ducks if he chooses to keep playing in North America.
Ducks general manager Bob Murray plans to contact Selanne next week to find out if he is close to making a decision on returning or retiring.
Senators general manager Bryan Murray, though, was among the many shocked when Alfredsson said he was ready to leave the only franchise he has played for in his 17-season NHL career.
"He indicated winning a Stanley Cup was an opportunity he couldn't pass up," Murray said. "He told me the two teams he was talking to. He told me he thought they were in a position ahead of us to make that happen."
While Alfredsson could have stayed in Ottawa to make more than the $5.5 million he will be paid next season by the Red Wings to chase the Cup, Horton is leaving a championship-contending team to be well-compensated by a franchise in Columbus that is without a postseason win in its 12 seasons.
"This is a team on the rise with great players, and I'm looking forward to being a part of it," Horton said.
Jagr, a five-time scoring champion and former NHL MVP, was able to continue his career during the lockout-shortened season when the Dallas Stars gave him a $4.55 million, one-year contract last summer.
After Jagr had 14 goals and 26 points in 34 games for the Stars, showing he could still produce, Dallas dealt him to the Bruins.
He had nine points in 11 regular-season games with Boston and 10 assists in 22 postseason games. He didn't have a goal in the playoffs but made key plays that didn't show up on the score sheet.
Jagr teamed with Mario Lemieux to help lead the Penguins win a pair of Stanley Cup championships as a teenager in his first two NHL seasons in 1991 and 1992, and was the league MVP in 1999.
AP Sports Writers John Wawrow in Buffalo, N.Y., Dan Gelston in Philadelphia and Rusty Miller in Columbus, Ohio, contributed to this report.