Armando Salguero

Armando Salguero: This performance shows Miami Dolphins not quite ready for big stage

Not good.

Not the Dolphins. Not the Cowboys. Not this night.

This preseason rehearsal that was supposed to show how ready these two teams are for the 2014 season instead showed that the Cowboys are, as one of their longtime employees confided, likely in for a season where their perpetual and unsatisfactory 8-8 records seem like the good times.

The Dolphins, meanwhile, showed their defense is probably what everyone has been seeing the past few years and expects for the coming season — a pretty solid, veteran group capable of stifling quality opposing talent such as Tony Romo and Dez Bryant and Jason Witten.

But the Miami offense?

The unit that is undergoing much change and hoping for much development while carrying much of the burden for 2014 is still, at best, a work in progress.

(Peanut gallery: But it’s the preseason. Relax. It doesn’t count.)

Well, that is true. It is the preseason and the fact the first-team offense has not scored a touchdown the past two preseason games doesn’t really count even if it does remind of the final two games of 2013 when that same unit managed only one score.

But, as quarterback Ryan Tannehill noted last week, this game didn’t count but it did matter.

It matters that Tannehill and the first-team offense managed only a field goal against a defense that is — not being unkind, just factual — bad.

The Cowboys defense was bad last year against the pass, ranking 30th out of 32 teams and the rush defense is only slightly more proficient, ranking 27th overall. Yet against this porous defense through which yards leak in waves, the Dolphins starters had almost as many turnovers (two) as points (three).

Those turnovers came on a Dion Sims fumble in the first half and a Tannehill second-half interception in which he threw into double coverage in the red zone. It was his final throw of the evening.

Tannehill finished the game completing 13 of 21 passes for 119 yards and that interception. And for the preseason, Tannehill has completed 28 of 41 (68.3 completion percentage) for 291 yards with one touchdown and one interception. Tannehill’s 86.5 rating is slightly better than the 81.7 he had last season.

Hey, improvement!

The Dolphins’ starting quarterback might have had a touchdown throw to Mike Wallace in the first half because the receiver was open deep behind the Dallas secondary and Tannehill saw him.

But as was so often the case last season, the duo failed to connect.

The ball sailed over Wallace’s head and it could be argued it was Tannehill’s fault for the overthrow or Wallace’s fault for failing to catch up to the pass or run a better route.

Blame the quarterback.

Blame the receiver.

It really doesn’t matter at this point whose fault it is because it hurts everyone.

It hurts the team that time and again last year this combination failed to deliver touchdowns on opportunities that begged big plays. It hurts the team that obviously the quarterback and his deep threat have not solved the issue of connecting on the deep pass.

It must be said Saturday night was not the major disappointment the first half suggested when starters were in the game.

Running back Knowshon Moreno, getting his first action in a Dolphins uniform, was Miami’s most explosive weapon. He not only gained 64 yards on 10 carries for an outstanding 6.4 average, but it was the manner in which Moreno ran that encourages.

Moreno ran with explosion. He ran downhill. There was no equivocation in the way he attacked the hole and the Dallas defense.

As Moreno continues to get healthier following his knee surgery and gets in better and better condition after missing weeks of training camp, the Dolphins will have an interesting decision whether to give him more carries than Lamar Miller while also using him on passing downs to protect Tannehill.

Moreno showed his value in that duty as well. He recognized and picked up a blitzing defensive back as Tannehill completed a third-down pass to Wallace to earn a first down.

Coach Joe Philbin, who said last week he had no clarity about what he was going to do with the starting right guard and left guard positions, also might have found some light about that issue.

Shelley Smith started at right guard and the unit seemed to work better when he was in the game. Dallas Thomas, who had started the previous two games at right guard, also got an opportunity with starters but on his first series he allowed a quarterback pressure on Tannehill.

Smith seems to be the better choice at right guard.

The left guard job continues to belong to Daryn Colledge. He was competing with Smith for the job and as Smith is the likely starter on the right side, that competition seems moot.

The Dolphins can build on those points. If they do, maybe the next time the starters are on the field they can manage more than one field goal.

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