DETROIT -- Nate Robertson is the one Tigers player who makes this area his year-round home. He doesn't have to worry about moving anytime soon.

While Jeremy Bonderman received a four-year contract last winter, and Dontrelle Willis signed on for three years after his trade last month, the question remained whether the Tigers would sign Robertson long term. If it was going to happen, this would be the time to do so -- two years before free agency.

As it turned out, the timing couldn't be much better. With a new three-year, $21.25 million contract, Robertson has some long-term security, and the Tigers have four members of their starting rotation under control through at least 2010.

"There's just a lot of great things happening right now," said Robertson, whose wife Kristin is expecting their first child next month. "We're driving here today to the ballpark, and it hasn't really hit me. You talk about this Kansas boy from a small town. We went out and cut firewood for a living when I was a kid. Now I'm playing baseball and signing a contract. I always thought that things happen for a reason."

There were several reasons behind this contract, foremost among them being the idea of stability in Detroit's rotation. The Tigers got an idea what it's like to look for starting pitchers on the open market a couple months ago when they weren't sure Kenny Rogers would be back. With Detroit's farm system thinner on starting pitching now than it was just a few months ago, and the possibility of the team being in that same position in a couple years, this was important for a team that could still be in a window to contend, if healthy.

The new deal essentially buys Detroit an extra year of Robertson's services, much like the Tigers did with Willis last month. Bonderman is also under contract through 2010, and Justin Verlander won't be eligible for free agency until after the 2011 season.

"We worked through a lot of issues," team vice president and legal counsel John Westhoff said, "and we're just very happy that we're able to come to this agreement and have four of our pitchers under agreement for at least the next three years."

Robertson will make $4.25 in 2008, similar to what he likely would've earned through arbitration. His salary then rises to $7 million in 2009 and $10 million in 2010. That 2010 salary will jump to $11 million if Robertson pitches either 400 innings in 2008 and 2009 combined, or 200 innings in 2009 alone.

"I think there was interest [in a long-term contract] as far back as last year," Robertson said. "There are a lot more variables that go into play. I'm not a guy that worries. That takes years off your life. I do my job. I work hard for it. And in the end, the way I was taught is you'll be rewarded for it."

The Tigers hope the deal also rewards them down the line. Both Robertson, who turned 30 last summer, and the team believes there's potential for him to grow.

The left-hander owns a 42-55 career record, but his ability to take innings is unquestioned. He has averaged 195 innings a year in his four full big league seasons, and his only missed time came last June with what was called a tired arm. He finished with a 9-13 record and a 4.76 ERA, allowing 199 hits over 177 2/3 innings with 119 strikeouts.

For his career, he's 24-22 with a 3.87 ERA and .722 OPS allowed before the All-Star break, compared to 18-33 with a 5.30 ERA and .826 OPS in the second half. He has traditionally had a rigorous offseason training program, but pitching coach Chuck Hernandez asked him to give himself more rest this winter before starting into his workout routine.

"He's had some adversity that he's had to fight through," assistant general manager Al Avila said, "and he's done so successfully. I agree with him. I think his better days are still in the future."

His offseason routine, of course, centers around Detroit. He was dealt from the Marlins to the Tigers just days after getting married, and it made sense for the couple to live in Michigan. They've been here ever since, and they haven't thought about leaving for warmer climates.

"We just came on up," Robertson recalled. "We planted roots. And for my wife and I, this has been home since our marriage began, so this is kind of a soft spot. I don't know why it hasn't convinced my teammates to come up as well, but they like the south when the weather gets cold."

Even if he didn't live around here, Robertson would have roots by longevity alone. With all the deals over the past couple years, only Brandon Inge and Bonderman have been with the team longer on a continuous basis. They and Fernando Rodney are the only players who have remained with the club from the 2003 team that lost 119 games, though Ramon Santiago was traded and came back.

"There's not too many guys still around," Robertson said, "but I'm glad I'm one of them."