Do not ask Boston's Sam Cassell if Rajon Rondo has improved dramatically.  The veteran point guard will only offer up, "What do you think?"

Maybe it is a stupid question, seeing as Rondo's third-year numbers are up across the board. Already third in the league in steals (2.23 per game), Rondo is also producing career bests in points (10.9 per game), assists (7.6 per game) and field goal percentage (51.7%). His player efficiency rating is also 4.8 points above the league average, thanks in large part to his ability to get into the lane.

"He kills on layups," said Knicks Coach Mike D'Antoni.

At this time last year, many members of the media questioned Rondo's experience and shooting ability. Now, with a championship ring in hand, it seems as though he is capable of meeting any challenge.

The best barometer for Rondo's progress might be the defenders being sent his way by opposing coaches. Sunday night against the Knicks, D'Antoni tapped Jared Jeffries — a 6-10 defensive specialist — to stand near the top of the paint, four feet from the ball, to deny the 6-1 guard the lane.

"If you lay off of him, he won't be getting lay-ups," D'Antoni said prior to Sunday's win over Boston. "He'll become a jump shooter."

As Rondo's success against smaller defenders has continued, coaches around the league have started to counter Rondo's speed with height. On Christmas Day, the Lakers went without a true point guard on offense for much of the game so that the 6-8 Trevor Ariza could defend him.

This strategy represents a marked change in how opponents approach Rondo. Last year, coaches concerned with limiting the Celtic's penetrating ability simply told their point guards to back off a few feet. That plan would eventually prove fruitless, as Rondo guided the Celtics to their 17th title.

"Just because somebody gives you a jump shot doesn't mean you have to take it," Celtics Coach Doc Rivers said prior to Sunday's loss at MSG. "I think that has been his biggest improvement. I think it gives you a running start to drive when you back off and that is basically what he's done."

But by mirroring Phil Jackson's defensive strategy, D'Antoni might have given the rest of the league a blue print for containing Rondo, and by extension, the Boston Celtics: Clog the lane with a forward, not a point guard.

New York's 12-point win over Boston on Sunday was due in part to a 1-of-7 shooting performance from Rondo. With Jeffries sagging into the lane, Rondo found himself playing only 26 minutes and giving way to backup, Eddie House, during many crucial moments.

"It was easy," said Rivers of his decision to sit Rondo for much of the game. "We were scoring more when he was off the floor."

Rondo had similar problems against Ariza, finishing the nine-point loss to the Lakers by shooting only 3-of-11 from the field. Jackson used the same strategy in Game 3 of last year's finals as well by using the 6-7 Kobe Bryant to block the lane.

"He didn't handle that well that night," said Rivers. "There will be nights when Rondo is not making shots or not making plays. On those nights you just hope somebody else steps up."

The trend in itself is a tremendous compliment to Rondo. He is only 22-years-old, and yet, as he goes, so go the World Champion Boston Celtics.

During Boston's 19-game winning streak, Rondo was the ringmaster. One night he would pick up a triple-double against Indiana (17 assists, 16 points, 13 rebounds), while others he was scoring 18 points in a third quarter against the Knicks.

Rondo's play this season has warranted more than just praise. His name is now circling in All-Star discussions.

"That would be a great honor," said Rondo. "Especially because of all the great athletes around this league."

He admits the suggestion is flattering, but has he been paying attention to any vote tabulations?

"Nah," Rondo shrugged. "Not really."

In a league low on modesty, Rondo's hard work and quiet demeanor are fresh alternatives. Drafted 21st overall in the 2006 NBA draft, he ignores obstacles, odds and comparisons.

"I measure myself against myself" Rondo said. "I compete every night against myself. I try to stay consistent and go out there and I bring it every night."

By challenging himself to improve, Rondo has earned a reputation as a defensive menace.

 "I didn't play defense until I got to the University of Kentucky," Rondo said of his time with former Wildcat Coach, Tubby Smith. "I was off thinking about offense, but now, I try and stay defensive-minded and do whatever my teammates need out on the court."

And while some may be happy to see their name among the league leaders in steals, Rondo continues to put pressure on himself.

"I wouldn't say I'm great at defense," Rondo added. "I have a lot to improve on, especially my weakside defense."

Rondo pushes himself in other areas as well. His three-point and overall field goal percentages are each up around 10% from his rookie season. Rondo has doubled his assists per game since 2006-2007 and now grabs nearly five rebounds per contest. For someone whose height and shooting ability were questioned so much, Rondo's ascent speaks volumes.

So when the Lakers and Knicks concoct a new defensive strategy for Rondo, the Celtics can take comfort in his history of perseverance. Quietly, he is confident in his ability to overcome any defense.

"It is what it is," said Rondo. "Some teams try and play me differently. They play all types against me and I'll be as ready as I can."

Boston's recent 2-4 stretch is just a speed bump in Rondo's development. Being guarded by forwards is a challenge he will meet just like any other: by continuing to work. As his shot and court-vision continue to develop, even this complication will subside. 

"I'm just trying to improve as a player," concluded Rondo. "I'm not really worried about it. (I've) got to get the rest of my teammates involved and continue to be aggressive."