The Cleveland Cavaliers are widening their scope in search of the rim protector that, even amid their best basketball of this young season, everyone knows they badly need.

Far more worrisome to the Cavs than their uneven 11-7 start is the lack of a proven presence at the rim to help stiffen their defense for the long term. That's why Cleveland, sources say, has been inquiring with the Memphis Grizzlies about the availability of reserve center Kosta Koufos among their various trade pursuits.

Sources say that the Cavs are well aware landing a quality big man likely depends on selling on potential trade partners to take back polarizing shooting guard Dion Waiters. Cleveland rates Waiters' talent highly, but sources maintain that the Cavs have let a number of teams know they are prepared to surrender him if they can acquire a difference-making center in return.

And Koufos, regarded as one of the league's more underrated interior defenders thanks to the limited minutes he gets behind Marc Gasol and Zach Randolph, would certainly qualify.

How willing the Grizzlies are to part with Koufos, meanwhile, remains to be seen.

It's naturally hard to see it at this early juncture no matter how blessed Memphis is with frontcourt depth. When you rip through the first quarter of the season at 16-4, there isn't much incentive to change anything.

Stay tuned, though. There are some significant differences between Koufos' standing with Memphis and the Cavs' long-running but ultimately unsuccessful attempts to convince the Denver Nuggets to bite on a Waiters-for-Timofey Mozgov swap.

In Denver, Mozgov is under contract next season on a highly favorable team option valued at $4.95 million. The Nuggets can't be faulted for wanting to keep a productive big man at that price for themselves when they know Mozgov can't bolt this summer. Koufos, by contrast, is an unrestricted free agent next summer whose camp, sources say, has made it known to Grizzlies management that it has less than pleased with the limited role carved out for the 7-footer over the past two seasons.

So ...

If the Grizzlies could add a scorer like Waiters for a player who could simply leave them without compensation in July, either to keep or trade themselves, you figure they'd have to consider it.

Especially since the Grizzlies, as formidable as they've looked so far, could certainly use another wing scorer to boost their own long-term aspirations, though it's a secret to pretty much no one at this point that Waiters -- judging by his struggles to adapt to a reserve role under first-year Cavs coach David Blatt -- doesn't want to come off anyone's bench.

The names of several fantasy trade targets to address the Cavs' frontcourt shortcomings have been in circulation for weeks. All of them, though, appear out of reach: DeAndre Jordan, Roy Hibbert and, yes, even Mozgov.

Koufos might prove to be, too, but Waiters-for-Koufos is a trade scenario that has to be monitored.

Even more so when you take note of the Cavs' interest in Grizzlies veteran Tayshaun Prince, as reported Friday by my ESPN.com colleague Brian Windhorst. The Cavs have the parts to assemble a deal to send Waiters to Memphis and take Prince's $7.7 million salary off the Grizzlies' hands in addition to acquiring Koufos.

Interesting possibilities all around to file away.