DENVER -- Rockies outfielder Michael Cuddyer never saw Sandy Koufax and Don Drysdale pitch for the Los Angeles Dodgers.

Heck, the left-right combo of the Dodgers had retired before Cuddyer was even born in March 1979.

Cuddyer, however, is a student of the game, and he's well aware that Koufax and Drysdale -- both of whom are enshrined in the Hall of Fame -- were among the elite left/right starting-pitcher combinations in the history of the game.

"Just look at the numbers," Cuddyer said.

From a firsthand experience, however, Cuddyer is quick to admit that the current Dodgers twosome of Clayton Kershaw and Zack Greinke has to be right in the midst of any conversations about the best left/right combos of all time.

"They compete and like to compete," said Cuddyer. "They have that kind of ability, that kind of mentality and that kind of work ethic. You will see a lot of players who have two of those attributes, but they have all three. That's what separates them from the norm."

That's what puts the Kershaw/Greinke combo right in the midst of discussions of all-time domination -- right along with Koufax and Drysdale, Frank Tanana and Nolan Ryan, and Randy Johnson and Curt Schilling.

Now, that's no knock on former Atlanta teammates Greg Maddux and Tom Glavine, who will share the stage at the Hall of Fame induction ceremonies later this month. The two Braves didn't overpower the opposition like the others. Maddux and Glavine were artists in their own right.

Kershaw and Greinke have that knack for pitching combined with an ability to simply overpower.

"What separates the best from the rest is work ethic," said Dodgers pitching coach Rick Honeycutt. "The way they approach everything every day. They do everything well, not just pitch well. They are into the game. They understand it. They field their positions. They hold runners. And they are always listening and looking for ways to get better."

That's why Kershaw and Greinke are among the elite.

Kershaw, 26, and Greinke, 30, were both selected for next week's All-Star Game, the only teammates among the 16 starting pitchers on the American League and National League All-Star rosters.

It's the fourth time for Kershaw, who is a two-time NL Cy Young Award winner and is in the first year of a record-setting seven-year, $215 million contract. Greinke, who won the AL Cy Young Award in 2009, is a second-time All-Star and is in his second season with the Dodgers after signing a six-year, $147 million free-agent contract prior to last season.

Neither, however, is satisfied. Both want to be better.

"You can have the stuff, but at this level, you can't just turn it on at game time," said Honeycutt. "There is the mental side. There are constant adjustments. Zack and Clayton have that ability in game to make adjustments.

"They know their roles. They go out there knowing they are supposed to pitch seven, eight, nine innings. That goes back to awareness. That's not taught. They are baseball guys. It's why they are No. 1s. They are off the chart in so many ways."

Given his age, Kershaw is still learning, although it's hard to imagine he is going to get a whole lot better. As if last year's 16-9 record and 1.83 ERA aren't good enough, Kershaw, despite a month on the disabled list, is already 10-2 with a 1.85 ERA this season. And he goes into a weekend start against San Diego with a streak of 36 consecutive scoreless innings that includes a no-hitter against Colorado.

"The slider is what separates him this year," Cuddyer said. "It's the difference in him to go from great to unhittable and unscoreable. He always had the slider and the curveball to go with that fastball, but usually one of them would be on, but right now he has both breaking pitches."

Cuddyer has an even deeper historical perspective on Greinke since both of them were longtime AL players before coming to the NL in the last couple of years.

"He is very analytical on the mound, during the game," said Cuddyer. "He doesn't just break down a game plan between starts, but when the game starts, he is constantly studying hitters and how they react to situations and pitchers. It's a cat-and-mouse game with him -- plus he has great stuff.

"The fastball is 95-97 [mph]. The slider is 92. He has the curveball, the sinker and change. You rarely see a pitcher with that kind of stuff so into the mental part of the game."

But then again, it's just that rare to see a left/right pitching combination on the same team that can compare with the Kershaw and Greinke.