As Mike Lowell packed his Red Sox uniforms before heading out of City of Palms Park on Friday, he understood the uncertainty. This was, after all, about to become uncharted territory for the 36-year-old.

Starting Sunday night, for the first time in Lowell's life as a baseball player, he is heading into a season as a backup. Sure, he hit ninth as a junior at Coral Gables High, and when he was first called up to the majors by the Yankees in September 1998, a whole week went by before the third baseman was playing every day.

But nothing like this.

"I don't know if I'm going to be good at it or not," Lowell said.

He understood the reality that if his Opening Day uniform said "Red Sox" on it, then starting most likely wasn't going to be option. Lowell's best chance at staying a starter came and went when Texas backed out of its trade with the Sox, and then drifted further away thanks to the signing of Adrian Beltre.

But there was always the infielder's hope that something might work out somewhere on the way to the season opener -- trade or otherwise. It didn't happen.

"I thought this was very much a possibility, yes," Lowell said. "I don't think anything I could have done in the spring could have changed my situation."

Even if he was healthy earlier?

"Nope," he said.

More at-bats? Hit .500 in the spring?

"I don't think it would have changed," Lowell continued. "They gave somebody $10 million to play third base."

As many twists and turns and ups and downs as Lowell has experienced throughout the offseason and spring training, perhaps there will be no greater level of frustration than Sunday night.

He will be sitting on the Red Sox' bench, and this time, unlike those days of March, there is no idea when a chance to prove his worth will come around again. It doesn't matter that in his last four exhibition games he has gone 6-for-11, punctuated by a hit and a walk in his only two at-bats during the Red Sox' 6-1 practice game win over the Nationals in Washington D.C. Saturday.

And the fact that Lowell has some of the better numbers of any Red Sox player against Yankees' starter CC Sabathia (5-for-19) won't change the situation. 

What he can take solace in is that, after a slow start and a slight derailment via a bruised knee, the infielder has done his part.

"Have I thought about what I'm going to do? Yeah. I'll ride the bike during the game. I'll swing off the tee. I know I can hit," Lowell said. "I feel great. If you see my at-bats the last few games, out of 10 [at-bats] I hit the ball six or seven times. Going into the last week of spring training that's where you want to be.

"It starts with seeing the ball well. I believe my mechanics and my swing are good, but if you're not seeing the ball well then there's a breakdown in your timing. That's why you need the at-bats. I'm seeing the ball well so I don't know why the results shouldn't be good ones."

A few questions have been answered: Lowell knows he can play a new position, first base, if called upon, while not having lost a bit of confidence in his offensive production. Still, as Opening Night arrives, there is still plenty of mystery to go around when it comes to figuring out what will happen to the Red Sox' right-handed bat off the bench.

"It's not like when I'm called upon I'm not going to be ready," Lowell said. "I'll be ready and I'll try to do well, but I don't know how it's going to play out. We'll see."