BALTIMORE -- Orioles manager Buck Showalter -- who joked about hoping to use his eraser on some mock lineups -- got his wish.

The O's have reached an agreement with free-agent designated hitter Vladimir Guerrero on a one-year contract, a Major League source confirmed to MLB.com on Friday evening.

"We got our cleanup hitter," Adam Jones said of Guerrero. "He's a masher."

"I'm pretty sure he's in great shape and ready to mash again. And I want to be the recipient of that, scoring the runs for him."

Guerrero's deal, which was first reported by ESPNDeportes.com, is reportedly worth $8 million, although the details are still being worked out by both sides. The Orioles have not commented on the signing, which won't be made official until Guerrero undergoes a physical early next week.

The 35-year-old Guerrero posted a .300 average with 29 homers and 115 RBIs last season with the Rangers, and was hoping to land a two-year contract at the start of the offseason. But with the designated hitter's market drying up, various reports the last several weeks hinted that the Orioles were Guerrero's best -- and perhaps only -- remaining landing spot.

President of baseball operations Andy MacPhail confirmed at last week's Fanfest that the organization -- although already over budget -- had been given the green light by principal owner Peter Angelos to continue negotiations. The result is a payroll that will exceed $90 million, and one of the deepest, power-laden lineups in recent Orioles history.

"[It's] definitely, hands down the best lineup since I've been here," said Orioles outfielder Nick Markakis. "You look at our lineup as much depth as we have, we've got to have the most depth on a lineup on a team in all of baseball."

As the longest-tenured Orioles player, Brian Roberts was in agreement.

"I am extremely excited to add a player of Vlad's caliber to our lineup," Roberts said. "I think it changes the whole complexion of our team. Can't wait to see how it all plays out."

Luke Scott will shift from designated hitter to left field with the addition, and he heartily embraced the move.

"I like it a lot," Scott said. "To have [Guerrero's] bat in our lineup and to move out to the outfield is going to be fun. It's going to be good for me to get a chance to play defense, [which is] something I enjoy doing."

Friday's agreement is just the latest addition for the Orioles, who have made a flurry of offseason moves, including adding power bat Mark Reynolds -- via a trade from the Arizona Diamondbacks -- and signing free agent Derrek Lee last month.

"Top to bottom, one through nine, this is a lineup that you just can't [coast through], you've got to be careful a little bit," Jones said. "It has no weakness now. Strength, speed, now you have that element of clutch and veterans with D. Lee and Guerrero."

Over his 15-year career, Guerrero has hit .320 with 436 home runs and 1,433 RBIs, and his arrival will help take the pressure off the likes of Scott, Jones, Markakis and Matt Wieters.

"We will be able to protect each other, which will be nice," Scott said of the O's vastly improved lineup. "[Guerrero is a] very, very, very dangerous hitter. [He is the] best fastball hitter I've ever seen. He can hit everything. He's a freak of nature. I mean that in a very good way. He hits pitches out of the ballpark that most people can't even foul off or get to."

The O's will use Guerrero as their full-time DH, and with Scott -- who is coming off a career year offensively -- in left field, the organization now has a logjam of outfielders in Felix Pie and Nolan Reimold.

While Pie can play center field and is the lone backup for Jones, Reimold still has an option left, which means he could be the odd man out and start the season in Triple-A. The organization is hesitant to make any last-minute trades before Spring Training, meaning it will be a crowded picture heading to Sarasota, Fla., for the first full-squad workout on Feb. 21.

But it's a problem the Orioles will take in stride.

"Anytime you add a player of his caliber, it's definitely a positive," Markakis said. "You look at his career numbers he's put up, great numbers, he's done great things for several different teams. And we are hoping he brings that to our table now."

"There's just a lot of options for us as a group. We've got a few guys that can DH and also play the outfield," added Scott. "So, the Orioles are in a good situation."