ST. LOUIS (AP) _ Ozzie Smith, heading into arthroscopic surgery on his shoulder, is certain he'll play again, and soon.

``I have all the confidence in the world that I'll be able to come back and finish this year,'' said Smith, the St. Louis Cardinals' 40-year-old shortstop. ``This will allow me to play as long as I want to.''

Smith, the major leagues' oldest opening-day shortstop since Luke Appling in 1950, was scheduled for surgery today in St. Louis. Team doctors have told him he'll probably be sidelined 4-6 weeks.

Smith's rehabilitation program begins on Friday. He referred to the operation as a ``cleanup,'' and said he wanted to play two or three more seasons.

Doctors will shave bones that have been causing inflammation and creating a calcium buildup that put pressure on nerves in the shoulder area.

Manager Joe Torre said if everything goes as planned, Smith could probably play as long as he wants. He won't, however, reach the number of plate appearances _ adjusted from 400 to 385 due to the strike _ necessary to automatically roll over his $3 million contract.

``I guess once they clean this thing out, he's going to feel like a young buck again,'' Torre said. ``I guess this has been coming for 7-8-9 years. Playing with pain for that long, I wonder how he'll react if it doesn't hurt anymore.''

Smith is the Cardinals' oldest shortstop since 44-year-old Bobby Wallace in 1918.

On May 18, Smith was placed on the 15-day disabled list for only the fourth time in his career, and had missed the previous six games. He has been undergoing daily therapy but recognized that it was not enough.

``I've played with pain in the past,'' Smith said. ``This year, I just got to the point where it was just uncomfortable. I just decided it was time to shut it down and get something done.''

Smith, in his 14th season with the Cardinals, is batting .250 with three RBIs in 68 at-bats. In his absence, the Cardinals have gone with rookie Tripp Cromer and Torre said he'd stick with Cromer at least for the time being. Cromer was batting .206 with three home runs and five RBIs, also in 68 at-bats.

Another option is Manny Lee, who is on rehabilitation assignment after spraining an ankle.

Smith tore his rotator cuff in 1985, but decided against surgery. He said the shoulder has been deteriorating gradually since then and since spring training he's had difficulty throwing the ball. For several seasons, he's gotten by with a quick release.

``I made the decision 10 years ago not to have surgery, and it was a good decision,'' Smith said. ``Here I am, 10 years later. But I knew and I was told that I was definitely going to get to this point.

``I was hoping it didn't happen until I was ready to quit.''

Smith said after his career he likely will have reconstructive surgery on the shoulder.

``That's an option after I'm done playing,'' he said. ``I'm not done playing.''

Smith is on the disabled list for the first time since June 16-30, 1992, when he had chicken pox.

Last season, Smith became the career assist leader, surpassing Luis Aparicio, and was the top vote-getter for the National League All-Star team, making his 13th All-Star Game appearance. He won 13 consecutive Gold Gloves from 1980-92.

One of the few goals keeping him going is 2,500 hits. He's 118 hits away.