PHOENIX -- In a perfect world, Eric Chavez's recovery from three offseason surgeries was going to be as smooth as the way he picks up a grounder. The progress was going to be steady, the news always encouraging and, under the right scenario, the finish line was to bring a start at third base in the March 25 opener against the Boston Red Sox in Tokyo.

Alas, best-laid plans are often like backs. They can get wrenched awfully easily.

So they were Friday, when the A's announced that Chavez received an epidural injection in his surgically repaired back and would be shut down for the next four to five days. The news throws into flux Chavez's stated goal of being ready for the opener and raises questions about his availability for the team's domestic opener in Oakland on April 1.

"It's just with the activity," head trainer Steve Sayles said. "He was doing very well, but if you mount activity over activity over activity, it can catch up with you."

Chavez received the shot from Dr. Mark Rubin of the Arizona Center for Pain Relief on Friday morning and did not return a call seeking comment. The injection, Sayles said, was "not to mask" the pain but rather to "quiet inflammation" in the back area. In October, Chavez had back surgery similar to the one received last spring by former A's center fielder Mark Kotsay.

Chavez had been participating in his own program this spring, taking grounders and facing live pitching. He was scheduled to begin playing in Cactus League games next week. But Sayles said Chavez had been complaining of gradually increasing stiffness, and when it didn't subside, the team decided to curtail his activity.

"It's not normal," Sayles said. "It's not the way things go usually. I don't think you want to have back surgery, and then need an epidural (31/2) months later."

How the setback will affect Chavez's intentions of being ready by the opener remain unclear. It now seems unlikely that he'll play in a game before mid-March. The A's depart for their Tokyo opener on March 19, and play two exhibition games before their regular-season opener against the Red Sox. The long flight and the effect that could have on Chavez's back also will be part of the consideration.

"We obviously don't have enough information yet to know anything definitive," A's assistant general manager David Forst said. "Until we see how he responds to the shot, we're not going to rule anything out."

Chavez, the longest-tenured player on the team (he's entering his 10th season) and its highest-paid (he's in year four of a six-year, $66 million contract he signed in 2004), brings with him one of the biggest question marks.

He appeared in only 90 games last season and missed the final two months with a variety of ailments. His numbers have plummeted steadily for the past two seasons, and his stat line in 2007 -- .240, 15 homers, 46 RBI and .752 on base-plus-slugging percentage were all career lows.

However, he also told reporters upon reporting that he hasn't had a pain-free day since breaking his hand in 2005, and he underwent three surgeries this offseason to take care of that problem. In addition to the back procedure, he had torn labrums in each shoulder repaired.

The volume of procedures has the A's taking a cautious approach with Chavez, and Sayles insisted Chavez has not tried to do too much too quickly. He also said the rigors of rehabilitating his shoulders did not lead to the back stiffness, and that his comeback from this blip won't necessarily be a slow one.

"You wait the four to five days, see how it went with the shot, and (return) the program maybe to the beginning," Sayles said. "But then you might be able to move that program quicker than you did originally. We just have to wait and see."

Contact Rick Hurd at rhurd@bayareanewsgroup.com.