"We've been pretty close for a while," Padres general manager Jed Hoyer said.
The tipping point for the trade that sent Tejada, 36, and half of the $2.33 million he is owed to San Diego for Minor League pitcher Wynn Pelzer likely came Thursday morning.
That's when the Phillies, one of the teams hot in pursuit of Tejada, turned their attention to completing the deal for Houston pitcher Roy Oswalt.
In swooped the Padres, who have been discussing adding depth in the infield for weeks, as well as someone who would give the offense a boost and provide some protection for three-time All-Star first baseman Adrian Gonzalez.
The Padres think they have that player in Tejada, who is expected to be at PETCO Park on Friday.
"He's a guy who won the 2002 [American League] MVP. He has a lot to bring and he's a tough out," Hoyer said. "We're hoping that getting him into a winning environment, he'll be energized."
Tejada was hitting .269 this season for the Orioles, with seven home runs and 39 RBIs in 97 games. He signed a one-year deal worth $6 million before the season.
"This guy can still play at a high level," Padres manager Bud Black said. "He's an experienced player who knows how to play, he plays with a lot of energy. Throughout his career he's been a great offensive player."
Hoyer indicated that Tejada will play "some third base, some shortstop and come off the bench a little bit." Hoyer is also confident that Tejada, who broke into the Major Leagues with the A's in 1997, still has something left in the tank.
The Padres were encouraged by the .346 average this season in 78 at-bats in Interleague Play as well as his track record and knowledge of the National League from having played the '08 and '09 seasons as a shortstop for the Astros.
"This move was made because it makes us better," Hoyer said.
That the Padres were able to swing a deal for Tejada without surrendering either of their top two pitching prospects -- right-hander Simon Castro or left-hander Cory Luebke -- was another bonus to Hoyer, especially because it's believed the Orioles asked for one or the other early on.
In Pelzer, the Orioles receive a 24-year-old right-hander who was 6-9 with a 4.20 ERA in 22 games this season for Double-A San Antonio.
Pelzer won 11 games and had a 3.94 ERA with Class A Lake Elsinore in 2009 and had 147 strikeouts in 150 2/3 innings.
According to a source, Pelzer's velocity was down a tick this season and he didn't show the kind of command he had a year ago. There's a thought he might profile better as a reliever than a starter.
"We certainly like Pelzer, but those top guys [Castro and Luebke] ... we think they'll be ready in the next year," Hoyer said.
Hoyer said that Tejada could see a lot of time at third base, especially against left-handed pitchers. Switch-hitter Chase Headley has struggled this season, hitting .195 against left-handers.
Hoyer even intimated that he's not reluctant to have Headley play some outfield, where he played in '08 and '09 when he moved from his natural position to left field when Kevin Kouzmanoff occupied third base.
"I wouldn't rule that out, but we're happy with the way Chase has played [defensively at third base]," Hoyer said.
As for Tejada, he was a late scratch from the Orioles' game Thursday against the Royals in Kansas City and was informed shortly thereafter of the trade.
"I just want to go up there and help them. I love winning and there's an opportunity there to be a winner," Tejada told reporters. "Now I go into a situation where I can get a ring. It's not easy to get a ring. It's a lot of hard work. Now I'm going to have an opportunity."
What can the Padres expect from Tejada?
San Diego special assistant Mark Loretta played with Tejada in '08 in Houston and said, "I would put him in the category of the best teammate I ever had. He's a guy with huge energy, someone who loves to play and get other people involved. He has one of those infectious personalities."
The Padres will make a move to accommodate Tejada on the 25-man roster but won't do so until Friday, the start of a three-game series against the Marlins.
There is some thought that Tejada's arrival could, for now, send struggling shortstop Everth Cabrera -- who entered Thursday's game hitting .201, with three of his six errors in the last seven games -- to the bench or possibly Triple-A Portland.
"Everth is a very good, young player who has struggled," Hoyer said. "I think, without a doubt, mentally he's pretty exhausted. This might take some pressure off him."
Finally Thursday, Hoyer intimated that he might not be done dealing. The non-waiver Trade Deadline is 1 p.m. PT on Saturday.
Corey Brock is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.