It was only about two years ago that people around baseball were speaking of Nick Markakis as one of the best young players in the game. If you lined him up against Ryan Zimmerman — to measure the franchise player of the Baltimore Orioles against that of the Washington Nationals, respectively — it was pretty much a toss-up. Markakis put up an .838 OPS in his first four seasons in the majors, just a hair behind the paces of Eddie Murray (.839) and Cal Ripken (.845).

Matt Wieters, left, celebrates with Nick Markakis, center, and Luke Scott. (Greg Fiume/GETTY IMAGES)

The drop-off in his performance, to be blunt, is staggering. (To be fair, however, Markakis is not alone in his struggles. All of the following in-their-prime star players, ages 27-31, are currently putting up OPS figures that are at least 200 points below their career marks: Dan Uggla, Adam Dunn, Hanley Ramirez, Alex Rios and Justin Morneau. Maybe there’s something in the water in the eastern half of the United States.)

So, what could be the problem with Markakis? There has been speculation recently that he is hurt. He has a history of shoulder soreness, dating to his amateur days as a pitcher, and some scouts have noticed his throws from right field don’t appear as strong as they once were. But the Orioles say Markakis is healthy – or at least they don’t have reason to believe otherwise.

“I think he’s fine,” Orioles Manager Buck Showalter said. But Showalter also acknowledged, “If there was something wrong with Nicky, he wouldn’t tell anybody.”

“We wouldn’t send him out there if we thought he was hurt,” said General Manager Andy MacPhail.

Markakis has also insisted he is healthy, describing his struggles as a matter of mechanics. And one American League scout who saw the Orioles recently concurred.

“I don’t see anything [at the plate] that would indicate he’s hurt,” the scout said. “What you see is a hitter with no confidence, who’s just trying to connect with the ball. He’s not using his lower half. It’s all upper body and wrists, which tells you he doesn’t have confidence in his swing, and he’s not able to drive the ball.”

But if not an injury, then what? Some Orioles insiders noted that Markakis was close with former Orioles hitting coach Terry Crowley, who was let go after last season. But new hitting coach Jim Presley is not seen as a radical departure from Crowley, who remains in the organization as a special-assignment consultant.

Some have speculated that Markakis is trying too hard to justify the six-year $66.1 million contract he signed in January 2009, pointing out that he suffered a significant fall-off from 2008 to 2009 (a drop in OPS from .897 to .801), in the first year of the new deal. But that still doesn’t explain this year’s nose-dive in year three.

Certainly, no one is questioning Markakis’s work ethic, or his efforts to get himself out of this awful slump.

“He does a lot of extra work,” Showalter said. “He’s doing all the things he can do, in some cases maybe too much. I know we’ve [spent] a lot of time and effort addressing it.”

The ironic part of Markakis’s struggles is that Orioles’ off-season moves – adding sluggers Vladimir Guerrero, Derrek Lee and Mark Reynolds – were made largely in order to provide him with better protection in the middle of the lineup. It hasn’t quite worked out that way (Guerrero, Lee and Reynolds are all hitting well below their career norms), but a lack of protection doesn’t adequately explain Markakis’s drop-off.

The Markakis problem has become the biggest issue in the Orioles’ universe – made even bigger by the team’s recent play. Following a three-game sweep of the floundering Oakland A’s, the Orioles (through Wednesday) find themselves just two games under .500 and 5 ½ games behind first-place Boston in the AL East.

The Orioles continue to show confidence in their franchise player, batting Markakis exclusively in the second and third spots in the lineup, despite his struggles.

“We’re hopeful that at the end of the year, his numbers will be back to where they always are,” MacPhail said. “I believe [that will happen]. He’s too good a hitter not to.”