Julio Lugo, once Tampa Bay’s shortstop, says he knew the Rays would improve.

AP / MARK DUNCAN

ST. PETERSBURG, Fla. — Kevin Cash and Julio Lugo know exactly what it is like to be a Tampa Bay Ray.

That’s because the pair of Red Sox players used to be Rays — Devil Rays, actually.

Lugo, who was originally drafted by the Astros in the 43rd round in 1994, signed with Tampa as a free agent on May 13, 2003. He spent parts of four seasons with the Rays before he was traded to the Dodgers in 2006. The shortstop eventually signed with Boston as a free agent Dec. 13, 2006.

“People are starting to give [the Rays] a little bit of credit now,” Lugo said. “It’s been a while, but they’ve done good. I loved it here. I played good. It’s strange [playing here in October] and they finally have some reporters here. They’ve had a good team, but I didn’t think they were going to do this good so soon. You have to give them credit.”

Cash, who originally signed with the Blue Jays as a non-drafted free agent in 1999, was acquired by the Rays in a trade for pitcher Chad Gaudin on Dec. 12, 2004. Cash spent two seasons in the Tampa organization, mostly at Triple-A Durham, and played 13 games for the Rays in 2005. He signed with Boston as a minor-league free agent in 2007.

During his brief stint with Tampa, he quickly realized the club would be very good very soon.

“I could see that it was coming,” Cash said. “I think [general manager Andrew Friedman and manager Joe Maddon] brought in a different tone when they came in. Relaxed isn’t the word, maybe a more positive environment as far as dealing with younger players. Joe, and the front office, has gotten them to respond more. There are a lot of young guys who are playing well.”

Lugo has experienced being a home player at Fenway Park and at Tropicana Field. He said he realizes this season the Trop has had some big crowds –– Tampa sold out eight games –– but nothing compares to home-field advantage at Fenway, where the Sox recently set a major-league record for consecutive sellouts, with 469.

“It’s tough to play in Boston [as a visiting club],” he said. “The fans are right on top of you and they bring more intensity. The Red Sox expect to win there. When you play at Fenway, it is the House of Pain. We’re going to have to find out how loud fans get here.”

jmcdonal@projo.com