Joachim Johansson announced his retirement over the weekend due to recurring shoulder problems. He is 25 years old. Is this a sign that more careers are being cut short by injuries now that we have power rackets and ball-grabbing strings?

By ball-grabbing strings I mean those Luxilon strings that enable a player to rear back and hit the ball as hard as humanly possible yet keep it in the court with the modern topspin stroke. Look at Roger Federer’s forehand. He hits the ball with a closed racket and his swing barely gets as high as his shoulder yet he catapults the ball over 100mph (161kmh) and still keeps it in the court.

I guess we should start by looking at the pre-power era players. Roscoe Tanner retired in 1985 after his elbow got so bad he couldn’t unload that fearsome serve of his. He wasn’t going to win a whole lot of matches without that serve. It turns out that Tanner had bone chips floating around his elbow and this was before sports medicine invented arthroscopic surgery.

John McEnroe, on the other hand, is still a top player on the senior circuit and he’s now 48 years old. McEnroe never swung hard at the ball whereas I can’t remember anyone who swings as hard as Rafael Nadal.

Nadal is only 21 years old yet he already has chronic problems with his feet and his knees – one injury no doubt leading to the other. Nadal winds up with his extreme Western grip and Popeye biceps and puts as much topspin on the ball as any human that ever lived. He also sets up far behind the baseline and runs many more miles than most tennis players because he seldom fails to get to the final of a clay court event. He had 81 straight wins on clay before Federer beat him in Hamburg last year. That’s a lot of wear and tear.

Bjorn Borg had an unorthodox stroke too, in fact, he probably ushered in the era of extreme topspin and he won seven straight French Opens on clay. But injury didn’t drive him from the game – it didn’t have a chance – burnout did. After losing the 1981 U.S. Open final to John McEnroe, he walked off the court and went straight to his courtesy car. He didn’t even stay for the award ceremony.

That’s a lot longer than Kim Clijsters lasted. She left the game last year at age 23 to have a family. Remember, though, that Clijsters turned pro when she was 14 years old.

So did Jennifer Capriati who was hit with both burnout and injury. She took time off from tennis when she was 17 years old and suffered through some teenage angst. There was some drug use and typical teenage acting out. She resumed her career and won three slams but she’s another sledgehammer player with a big serve and a shoulder injury finally seems to have ended her career for good.

Okay, so burnout and injury are nothing new, but there is a theme here. If you’re a power player who depends on slamming the ball as hard as you can from the baseline, you’re going to wear yourself out. If you’re a graceful mover who can take the game to your opponent and finish points off early, you should have a long and relatively injury free career.

If the theory holds, what are my career longevity predictions for current players?

Maria Sharapova is a big server and big hitter who doesn’t move that well and hates coming to the net. She’s already had shoulder problems and could have more. On the other hand, Jo-Wilfried Tsonga should do well because, though he’s a big server and a big hitter, he can finish points off at the net and that shortens points and preserves his body.

Finesse players should live long and prosper too, though they may not win many tournaments. Fabrice Santoro has the record for number of grand slam appearances. His forehand is a two-handed slice for heavens sake. Santoro will still be playing senior tennis when he’s 60 years old and he’ll still be driving Federer crazy should Federer choose to play senior tennis.

Of course, the theory doesn’t always work. Andy Murray is a walking injury and his game is all about finesse. Anna Chakvetadze is most often compared to Martina Hingis but Hingis had to retire for three years with foot problems. And then there is unforeseeable disaster. Chakvetadze is still recovering from the shock of being robbed at gunpoint at her home in Moscow in late December. Her father was beaten by one of the robbers.

Meanwhile, life on the professional tennis tour goes on so I might as well give you today’s injury report:

Serena Williams has pulled out of this week’s indoor Paris event saying that she needs surgery. For what? We have no idea. Serena controls her channel of information, not the WTA. John Isner has a stress fracture and will be gone for as long as it takes to heal. See what I mean about power players with big serves?

What are your predictions for the career longevity of current players?

American Jesse Witten had match point on Bruno Echagaray’s serve in a challenger event in Dallas, Texas, last week when a lineswoman called a foot fault on Echagaray’s second serve. Witten is an American player and Echagaray is from Mexico.

The score was 6-5 in the third set tiebreaker when the call was made. Echagaray lost his temper as you’ll see. Even the announcer was stunned. On the one hand, if you see an infraction you call it. On the other hand, when was the last time a foot fault cost someone a match?

What do you think?

Lindsay Davenport returned to Fed Cup play and and lost her first ever Fed Cup match on U.S. soil.

Next week is Davis Cup week for the men and this week is Federation Cup week for the women. It’s early in the Fed Cup cycle so we weren’t looking for any titanic battles, most of the ties looked foreordained.

For instance, the U.S. started its tie with Germany by throwing Lindsay Davenport against Sabine Lisicki. I had never heard of Lisicki. Part of that is on me – she made it to the third round at the Australian Open as a qualifier – but she’s hardly a household name. Now I definitely know her name. She beat Lindsay rather easily, 6-1, 7-5, to put Germany up 1-0.

Lindsay is still making her way back onto the tour after having a baby last year and I hadn’t see her play till she met up with Maria Sharapova in Melbourne. Lindsay looked flat-footed and slow as Sharapova hit her off the court but how could I judge Lindsay’s prospects from that encounter? Sharapova pushed everyone off the court in Melbourne.

Lindsay was 13-1 last year and she’s 6-1 this year but Lisicki pushed her off the court too. Lisicki hit behind her, in front of her, and went for more than the average number of drop shots. Lindsay might have had trouble warming up in the first set because it was cold at the La Jolla Beach and Tennis Club in balmy San Diego. Coulda been the ocean breeze I suppose.

But after Lisicki gave away a break of serve with four double faults in the second set, Lindsay couldn’t close out the set. Facing break point at 5-3, Lindsay couldn’t run down a shot to the corner. She had a set point against Lisicki in the next game but stood there flat footed as yet another shot landed in the corner.

Lisicki pulled that game out with an ace and a beautiful inside out forehand that dropped over the net short and curled out of the court. She’s a gutsy player – she won this match despite eleven double faults and 33 errors – but I’m not feeling all that positive about Lindsay’s future at the moment. If the 130th ranked player can move Lindsay around at will, surely many other players can do the same thing.

If you were wondering if Lindsay lost because she played poorly or Lisicki played so well, here was Lindsay’s answer to that question after the match:

I think it was probably a little of both. I mean, obviously disappointed with the way I went out there and played. But at the same time, she played very well and had a lot to do with that.

Lindsay also said something rather interesting about Lisicki’s breakthrough at the Australian Open:

I think the Australian Open was the first big tournament she played well at, and she’s young. It’s a lot easier to play so well when you’re young.

It’s easier to play well when your young. Now that is a backhanded complement. Either Lindsay is feeling old or she’s feeling a bit sorry for herself. She’s referring to the fact that Lisicki had no pressure on her because she wasn’t expected to win the match but Lisicki was also playing a three time slam champion who is now the all time money leader of the women’s tour and she won the match in straight sets.

Fed Cup rookie Ashley Harkleroad saved Lindsay’s butt with a 6-1, 6-3 win over Tatiana Malek in the second match to even the tie at 1-1. Lindsay and Ashley will play reverse singles tomorrow and Lindsay will play the doubles match with Lisa Raymond.

Did you see the huge pink, bejeweled ring on U.S. Fed Cup captain Zina Garrison’s middle finger by the way? Wow, that is something to behold. Lindsay doesn’t have the company of the Williams sisters to help her this week. I did have a quick thought that it might be a silent protest to the end of Zina Garrison’s tenure as Fed Cup captain. Mary Joe Fernandez is a Fed Cup coach this year and will take over for Garrison next year.

There’s a bit on intrigue in the Fed Cup tie between Russia and Israel too. Sharapova is playing in her first Fed Cup match so that she can qualify for the Olympics. Missing, though, are Svetlana Kuznetsova and Nadia Petrova. There is speculation that they didn’t want to play on a team with Sharapova. They’re probably not happy that they are the players who did all the heavy lifting that led to a Fed Cup championship and here comes Sharapova to make a cameo appearance just so that she can win a gold medal.

Russian player Dinara Safina did turn up but she lost to Israel’s Shahar Peer. Things might sort themselves out. The U.S. could well win the its tie and Russia is likely to beat Israel. Still, it’s not the foregone conclusion we thought it might be.

Novak Djokovic receives his 2008 Australian Open award after winning the final over Jo-Wilfried Tsonga.

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