Little to gain with this pain

How's this for eerie: In 1999, the San Antonio Spurs won the NBA championship. Then Tim Duncan went to Puerto Rico to help the U.S. qualify for the 2000 Olympics. Then, late in the 1999-2000 season, Duncan hurt his knee and the Spurs were unable to defend their championship. Fast forward to 2003, when the Spurs win the NBA championship, then Duncan goes to Puerto Rico to help the U.S. qualify for the 2004 Olympics, then Duncan injures the same knee he hurt in 1999.

This time, it wasn't quite as serious, and Duncan has returned to play for the Spurs, though hardly at the level or minutes he was before the injury in late February. Before then, Duncan had played at least 40 minutes in 12 consecutive games which, perhaps, accounted for some of his problems coming off a summer of play in the Olympic qualifying tournament. Since returning full-time on March 18, Duncan has played 40 or more minutes in a game just once (and that was exactly 40), and is averaging just 32 minutes per game. Duncan also has scored fewer than 20 points in more than half of the Spurs' games since. It hasn't hurt the Spurs, who, even with less Duncan on offense, have streaked to the finish again, albeit primarily with their defense.

How was NBA history affected by Duncan's injury in 2000?

Spurs coach Gregg Popovich believes that the '99-'00 team would have repeated. Who knows what kind of run San Antonio would have had if Duncan hadn't got hurt and if the Lakers hadn't broken through in 2000 when even Phil Jackson doubted it was possible -- in his first season teaching a new system to a Lakers team that had been a longtime playoff failure at the time. After all, it was the Spurs who knocked out the Lakers last year. Would they be the ones with the three-peat, and perhaps more?

When the playoffs arrive, there are all sorts of angles to examine. There are the matchups and the breaks. In 1994 and 1995, the Rockets avoided the SuperSonics in the playoffs. Seattle had knocked out Houston in 1993 and always gave the Rockets problems. Perhaps the Rockets would not have won their titles if they had to go through the Sonics. There are the individual matchups to examine, the momentum from the stretch run, the games between the teams during the season, home-court advantage and the schedule.

But perhaps nothing is as significant as injuries.

It's an often overlooked team, but the 1989 Lakers were on the way to immortality. They had won two straight NBA championships and were cruising toward a third. They were 11-0 in the playoffs and coming off a sweep of a 55-win Phoenix team. They were looking for the first three-peat since the Boston Celtics of the 1960s (Pat Riley already had obtained a copyright of the three-straight-titles term) and were looking to become the first ever team to go through the postseason undefeated.

Instead, Byron Scott and then Magic Johnson got hurt, and it was the Pistons who swept a Lakers team run by Tony Campbell and David Rivers.

It's obvious. If your best player is hurt, you are not going to be the same team. But injuries to key supporting players can change a team's rotation and be the difference between a championship and a disappointing finish. So here's a look at the top 10 injury concerns heading into the playoffs.

1. Kobe Bryant, Lakers.
Injuries: Shoulder, psyche.
Playoff prognosis: Perhaps all the Lakers problems, to say nothing of Bryant's, started in the playoffs last season when Bryant stretched on a dunk and his shoulder was never the same. When he went for offseason surgery in Colorado, his off-the-court problems began. Though he's not wearing anything to protect his shoulder, a hard pick could put him in trouble again. Perhaps more significant is his fragile mental state. And can you blame him? There's not as much talk about it anymore, but Bryant remains an accused felon out on bail. He could be in prison for years. It has to weigh on a person and cause some erratic behavior. One thing has been made perfectly clear throughout the Lakers' season, though: Karl Malone and Gary Payton are not quite what they were, and the Lakers will not win a title without a healthy Bryant, mentally and physically.

2. Tim Duncan, Spurs.
Injury: Left knee.
Playoff prognosis: It is a wounded knee. The Spurs are being very careful, and Duncan hasn't played his usual quota of minutes the last month. Sure, Manu Ginobili and Tony Parker have played well, as has Bruce Bowen. And the defense has been terrific. But the Spurs often run into long scoring droughts. After all, where would they have been last season in the playoffs without Steve Kerr? They need a healthy Duncan to be an offensive threat or they have no chance to repeat.

3. Jason Kidd, Nets.
Injury: Bone bruise in left knee.
Playoff prognosis: Like Kenyon Martin said a few weeks back when someone asked him about the Nets' missing fast break. He pointed to the injured Kidd and said it was sitting on the bench. The Nets don't go very far without Kidd. They were a losing team before he came to Jersey, and even though they're better than they were then, he's still the difference. He's sat out late in the season with knee problems that trace back to last summer with the Olympic team. He needs to be pushing the ball for the Nets to have any chance to return to the Finals for a third straight season. Few believe he can at that level if his knee isn't better, which doesn't seem to be the case.

4. Bobby Jackson, Kings.
Injury: Strained abdominal muscle.
Playoff prognosis: Yes, we've heard and seen all about Chris Webber. He's not what he was. The career 49-percent shooter shooting less than 42 percent since his return from a serious knee surgery. That's because he's not getting the easy baskets, fast break dunks and quick-move layups. He's unable to finish due to the knee. The Kings came down the stretch a .500 team as they got Webber more playing time to get his knee back quicker. But they miss Jackson as much. Even though he comes off the bench, Jackson may be the toughest guy on a team that isn't very physical -- a guy who provides easy baskets with fast breaks and a spark plug-type player who energizes what can be a casual team.

5. Chauncey Billups, Pistons.
Injury: Sprained left ankle.
Playoff prognosis: The Pistons have become the favorites in the Eastern Conference (despite the Pacers' conference-leading season) after blowing away Indiana in their only game since acquiring Rasheed Wallace. He's certainly a key element and has been bothered by minor injuries. But the Pistons' key may be Billups. He was hurt last year in the playoffs -- missing three games and then playing not at full strength when the Nets swept the Pistons. And he's been out at the end of the regular season with ankle problems. While the Pistons can defend as well as anyone in the league, and certainly in the East, they won't be able to score enough and spread the floor without Billups' perimeter threat and scoring mentality.

6. Michael Olowokandi, Timberwolves.
Injuries: Knee, desire.
Playoff prognosis: The Wolves' Big Three isn't enough, as good as they've been. Because they play on the perimeter too much. Perimeter teams have won the NBA title, but they had to be great passing and shooting teams, like the 1970 Knicks. However, those Knicks had an inside presence in Willis Reed. For most of the playoffs, anyway. Sure, Kevin Garnett's rebounding numbers are good, but they need Olowokandi to hit the offensive boards like he did the last few weeks of the season and be the defender to take on and stand up to the big, inside players in the West. If Garnett has to do it alone, the Timberwolves won't have quite enough.

7. Pau Gasol, Grizzlies.
Injury: Strained arch in right foot.
Playoff prognosis: The notion is that the Grizzlies are a star-less team and can do it with Hubie Brown's manipulation of a 10-player rotation. Wrong! They need Gasol, who's underrated and taken for granted. He hasn't missed a game in his career until a strained arch sidelined him late in the season. The Grizzlies predictably collapsed. He's their leading scorer and rebounder, and while his numbers and minutes aren't huge, he's their one, true reliable offensive threat in the post.

8. Ron Artest, Pacers.
Injury: Torn ligament in left thumb.
Playoff prognosis: It seems Artest has put his emotional issues behind him. However, we haven't seen him with much adversity this season, so the jury remains out on whether he can hold up in the playoff cauldron. Whether his troublesome thumb can also hold up remains an issue. He had surgery after the All-Star break and was back practicing in less than two weeks. But with the way he grabs and holds on defense, Artest is vulnerable to reinjuring the thumb. Although his shot selection isn't in any playbook, Artest's defense and uncanny moves in the post are the extra factors that could take the Pacers to the Finals. Without him, they're in trouble.

9. Baron Davis, Hornets.
Injury: Sprained left ankle.
Playoff prognosis: Davis was the best player in the NBA during the first month of the season when the Hornets started 17-7. But he missed about a dozen games with an ankle injury, and the Hornets staggered and have never recovered. Davis also became something of an afterthought because he stopped going to the basket when he did play. As a result, his shooting fell below 40 percent for the season. But the Hornets still have the best talent in the East, especially if Jamal Mashburn is able to return from right-knee problems. With All-Star Jamaal Magloire and all-role player P.J. Brown, the Hornets could still be a threat for an upset, but they need the aggressive Davis.

10. Dwyane Wade, Miami.
Injuries: Wrist, foot, ribs.
Playoff prognosis: It's been a medical journey for the third rookie. The attention has been on LeBron James and Carmelo Anthony, but Wade has been integral part in Miami's improbable run into the middle of the Eastern Conference. With Lamar Odom and Caron Butler returning to form, the Heat has a considerable number of weapons and a chance for some upsets. But Miami needs a healthy Wade, a versatile rookie who can run the offense and supply the athleticism to support Eddie Jones and Brian Grant.

Sam Smith, who covers the NBA for the Chicago Tribune, is a regular contributor to ESPN.com.