Kansas City, Mo. ? The Kansas City Chiefs have glimpsed their future, and it does not look good.

Although neither has said for certain, this could be the last season in the magnificent careers of left tackle Willie Roaf and right guard Will Shields, who have made 10 Pro Bowl appearances apiece and solidified one of the finest offensive lines in the NFL the past few years.

Roaf, 35, is sidelined by a hamstring injury that’s bothered him most of the year, and Shields, 34, is slowed by various aches and pains brought on by 13 years of NFL pounding.

As a result, the offense ranks nowhere near the level it’s been. Most critically, quarterback Trent Green is ducking for cover on almost every passing down.

And the Chiefs stand 5-4 after a 14-3 loss Sunday at Buffalo that put them two full games behind Denver (7-2) in the AFC West.

Shields talked about retirement last summer. And something Roaf said several months ago could bring shudders to Chiefs fans who watched the debacle in Buffalo:

“Next year, the Chiefs might not have Will and me.”

The offense’s decline reached its lowest point in several years in the Buffalo game. Green had three interceptions and a fumble while getting sacked six times in the Chiefs first touchdown-less game since the 2002 regular-season finale.

Running back Larry Johnson played well in the first game since three-time Pro Bowler Priest Holmes went on injured reserve, running for 132 yards on 27 carries.

But as the line struggled, neither Johnson nor anyone else in a Kansas City uniform ever got within 15 yards of the goal line.

“The first thing you don’t do is panic,” coach Dick Vermeil said Monday. “Even as bad as we are, we’re the ninth-ranked offense in the NFL. The trouble is, you keep looking at what we were. We’re not that. We’ll get some of that back. You don’t panic, but you’d better adjust.”

Also a problem is right tackle. John Welbourn, 29, whose best position is guard, took over at right tackle against the Bills and struggled.

But taking most of the blame, and perhaps unfairly, is Jordan Black. The third-year pro out of Notre Dame has spent the year shuttling back and forth from left to right tackle.

He was supposed to be a candidate to start at right tackle until Roaf got hurt in the opener. Black went back to right tackle when Roaf came back, but has returned to the left side of the struggling line now that Roaf is back on the injury report.

And he’ll probably be there for a while. Roaf indicated Monday he probably wouldn’t be ready for this week’s game at Houston.

“I guess I’ve got to get used to the fact that I’m flipping around,” Black said. “I’m not trying to make excuses for myself or anything like that. But it’s difficult going right, left, right, left. I feel the most comfortable when I’ve had time to practice a position. The more practice I get, the more time I get on the field to prepare for a position, the more comfortable I feel.”

Black said he didn’t know when Roaf would return to reclaim the position he had played with such skill.

“I just take it week to week,” he said. “I’m always going to hope that Willie gets better as soon as he can. It’s hard having a guy like that out of the lineup. But when he’s back, he’s back, and we’ll see what happens to that point.”

Coaches, in the meantime, are searching for ways to help the blockers.

“The first thing we can do is stay out of the two-minute offense,” Vermeil said.

“The biggest breakdowns in pass protection (at Buffalo) were in the last nine minutes of the game when we went no-huddle. Those were the glaring problems.

“In the first half, we had a sack and a pressure. We were doing OK.

“Then we got into the have-to-throw the ball, down-by-11, sit-back-there-and-throw-every-time (mode). Then we had problems. It magnified the problem and makes it seem like you had problems the entire game.”