There are all sorts of reasons to believe the Orioles will remain competitive in the American League East and make a strong bid to reach the postseason.

The starting rotation, however, is not one of them.

The Orioles just completed the first quarter of their schedule and entered this week's road series against the Houston Astros at the top of the division. This apparently has come as a big surprise to everyone who figured them for the other end of the standings, but they have gotten a surprisingly solid performance from a group of starting pitchers who were cited as the main reason for the club's lack of preseason respect.

So, fans have every right to thumb their noses at the so-called experts and bask in the glory of an impressive start … as long as they prepare themselves for the unpleasant possibilities that lie directly ahead.

The starting pitchers — with the obvious exception of struggling Ubaldo Jimenez — have pitched just well enough to allow us to remain in denial about the true potential of the rotation.

They deserve credit for staying in the upper half of the American League ERA rankings (entering Tuesday's games). But they'll need to improve on their 4.44 rotation ERA to be consistently competitive, and the organization does not have enough pitching depth to offset the inevitable obstacles that every team encounters over the course of a long season.

Sure, there's a chance that Chris Tillman will pitch like a true No. 1 all season. He has done it before. There's even the likelihood that Kevin Gausman will continue to develop into a top-of-the-rotation talent.

Then what?

You do realize that the Orioles have been muddling along with two inexperienced starters who came to spring training to compete for the fifth slot in the rotation amid the hope that the club would sign a free agent who would leave both of them available for the “Norfolk Shuttle.” Tyler Wilson has pitched pretty well so far and Mike Wright has had some solid outings, but nobody anticipated that they would fill the Nos.?3 and 4 slots while free agent Yovani Gallardo recovered from a sore shoulder.

The Orioles are banking heavily on Gallardo's coming back from his bout with shoulder tendinitis ready to be the dependable pitcher he has been throughout his career. He has spoken highly of the strengthening program the team's medical staff has devised for him and seems confident he'll come back in better shape than the pitcher who signed late and missed a chunk of spring training.

Still, that's a big if to go with the uncertainty surrounding the two young pitchers in the rotation who have yet to prove they can pitch effectively when they get to the third time through an opposing batting order.

Wilson and Wright are showing promise, but they are also showing their stuff to the rest of the league, which will scout their weaknesses and push back hard during the second half of the season. Throw in one more great unknown — just how many innings Gausman will be able to pitch this year after throwing just 1342/3 last year and starting this season on the disabled list with a sore shoulder.

The Orioles actually had better starting depth during their disappointing .500 season last year. They had Wilson and Wright in reserve before Wei-Yin Chen bolted as a free agent and Miguel Gonzalez could not hold his place on the roster this spring.

Vance Worley is the only fallback candidate on the major league staff, and it appears that the Orioles are intent on stretching out T.J. McFarland at Triple-A Norfolk, since he did not get called up when they traded left-handed reliever Brian Matusz.

What you see is pretty much what you're going to get, until at least the July trading period, when some hopeless team might be willing to part with a quality pitcher for economic reasons. But the Orioles' depth problems also figure to hamstring them in a midseason trade market they used to acquire several useful pitchers over the past four seasons.

Baseball operations chief Dan Duquette has worked his strange magic before, but finessing this starting rotation into — and through — the playoffs might be too much to ask.

peter.schmuck@baltsun.com

twitter.com/SchmuckStop

Read more from columnist Peter Schmuck on his blog, “The Schmuck Stops Here,” at baltimore sun.com/schmuckblog.