Novak Djokovic bailed out on his commitment to take part in the lucrative International Premier Tennis League as a Singapore Slammer last week, conceding: "It's been a long year for me and my body needs some extra time to recover. I wish the team the very best and will join them next year."

In so doing, he chose much-needed rest over a spectacular payday that few of his elite peers have been able to resist.

It would seem a crushing blow to the hopes of the Slammers, one of five IPTL franchises. But before the red clay of Ghent, Belgium, had even dried in Andy Murray's socks, the Scot had stepped in as a replacement for Djokovic, and with a wingman no less -- fellow two-time Grand Slam champion Stan Wawrinka.

It's ironic. The WTA lost talent left and right to injury and fatigue this fall, despite having cut back its season to 10 months in 2009. The men still play deep into November, but both groups eschew maximum rest and recovery to spend their ephemeral offseason globetrotting after money.

Well, it is lots of money.

Upon launch last year, the league set a $10 million-per-team salary cap. Subsequently, it was widely reported that the league spent in the vicinity of $25 million on talent, with top singles players like Roger Federer (who was a replacement for an injured Rafael Nadal) earning $1 million per night. The workload: a one-set singles match featuring no-ad scoring and a 13-point "shootout" tiebreaker at 5-all (Federer also played in the doubles and mixed sets).

It may seem like crazy money, but it isn't out of line on the low-stress exhibition circuit, where a million-dollar payday per appearance is a reality. But with a five-city, three-week season, the IPTL takes the familiar exhibition to another level.

In its second year, the lineup includes (for some if not all matches) Serena Williams, Nadal, Federer, Maria Sharapova, Murray, Wawrinka, Kei Nishikori, Ana Ivanovic and others. The question arises: Is this league a good thing, offering elite players a chance to play a little casual tennis, pick up a bunch of cash and remain limber -- or are the players unwisely risking their longevity in order to fatten their bank accounts?

If you were struck by the frequency of injuries reported by players in September and October, it may seem like the latter. Williams, Sharapova, Nishikori and Marin Cilic were among the IPTL chosen who struggled with or mentioned injuries in 2015. Federer, 34, is no spring chicken. Nadal is trying to regroup for 2016.

Tennis players often cite the grind of life on the road as one of the chief factors in late-season burnout. Yet here are some of the most nomadic of the road warriors in sports, spending up to three weeks of December on what is essentially a second Asian swing. Only a handful of the stars -- Nishikori, Leander Paes, Nick Kyrgios, Samantha Stosur -- are from the region.

One side effect is that tennis no longer goes dark. The only players resting are the journeymen who have less need for rest than for earning opportunities -- the precise opposite of the elites. Like golf, tennis is becoming a "wraparound" sport with no real offseason. But tennis certainly is more physically grueling, so the wrap is more dangerous.

There's another problem here. As in golf, the lack of an offseason means that fans don't get a chance to miss their sport and build up enthusiasm and interest in the new year.

Of course, nobody is going to confuse the IPTL with tournament tennis. It's essentially modeled after Billie Jean King's brainchild and lifelong pet project, World Team Tennis. Like WTT, which flourished for a period in the mid-1970s, the IPTL puts an emphasis on entertainment rather than competitive credibility. Both exhibition leagues do bring the game to people and places (in the case of the IPTL, Asia) the ATP or WTA may not reach.

"I'm going to five cities in three weeks," IPTL rookie Milos Raonic said in an interview on the IPTL website. "That's five cities I've never played in, so that's pretty special."

The funny thing is, Raonic sounded like he meant it. Or maybe he's just happy that Djokovic has stepped aside, meaning that someone else will get a chance to win something this year.