If this was 2003, everyone might be suspecting Marlon Byrd of rampant steroid use.

Not only is the Cubs’ center fielder having a career year — Byrd is hitting .316 with 10 homers and an .855 OPS heading into Tuesday night — but he’s doing it with the help of infamous BALCO founder and steroid pusher Victor Conte.

According to Yahoo Sports, Byrd takes a daily regimen of supplements for muscle growth and energy sustainability that’s outlined and prescribed by Conte.

Byrd takes several amino acids and proteins before games, followed by a postgame powder to accelerate post-workout recovery. Before bed, Byrd takes a long-lasting protein and a zinc-laden pill called ZMA-5 which is vital for recovery, according to Conte.

"It is widely known that zinc helps speed up the healing process of bruises and plays a major role in tissue repair," Conte told Yahoo Sports.

The regimen has worked for Byrd, who has seen his normally mundane numbers increase every year since forming an alliance with Conte nearly 30 months ago.

In 2008, Byrd resurrected his career in Texas by posting an .842 OPS in 122 games. In 2009, the 32-year-old doubled his career high in homers with 20 for the Texas Rangers, and he recently made his first All-Star team for the Cubs in 2010.

But unlike the rest of his All-Star compadres — or any other big league players, for that matter — Byrd is the only one to use supplements prescribed by Conte, who is notoriously known for giving steroids to Barry Bonds, Marion Jones and Tim Montgomery.

"Nobody I know uses it," Byrd told Yahoo Sports. "And I’ve recommended it to all my teammates. I recommend it to everyone. Everyone is always searching. I know what works for me, and I try to pass that on. But they are reluctant."

Can you blame them? In an era where buying anything at a drug store receives a glare from Bud Selig and his crew, the Byrd-Conte relationship is crossing barriers that most players wouldn’t dare, in fear of tarnishing their reputations.

But Byrd remains fixated on his routine because it’s given him so much success over the last few years. According to Byrd, it’s a necessary part of his life.

"The keys for me are food, supplements and sleep," Byrd told Yahoo Sports. "Stay on the same schedule of food every day, and you are going to be a better player, even if it is a placebo. Wade Boggs ate chicken every day. That was his thing. Me, I believe in taking supplements before games."

Byrd might not be the Hall of Famer that Boggs was, but he’s been “the man” at Wrigley Field this year.

"Marlon’s done a nice job for us, a really nice job," Cubs manager Lou Piniella told Yahoo Sports. "He’s played hard. He’s got some energy to him."

Maybe Piniella should order the rest of his Cubs players to meet with Conte. Chicago is 10 1/2 games out of first place in the NL Central.