2 pm Saturday: UM's investigation into players who might have used cars from a South Beach luxury car rental agency, in exchange for future promises, has expanded and now includes UM receiver Stacy Coley, according to a source with direct knowledge.

As we have previously reported, Al Quadin Muhammad and Jermaine Grace also are being investigated by UM for using cars from South Beach Exotic Rentals. UM, not the NCAA, is handling the investigation.

UM has declined to say if any of the players will be suspended. Some UM players are expecting short suspensions for the players, but it remains unclear if that will happen.

UM is still in the process of determining what, if any, discipline will be doled out.

DOLPHINS TALK

Well, at least we can all stop complaining about the offense this week. Ryan Tannehill was terrific (12-20, 162 yards, two touchdowns, 119 rating). Kenny Stills was dynamic (3 catches, 71 yards). And though starting right guard Jermon Bushrod allowed a sack, rookie starting left guard Laremy Tunsil was outstanding in pass protection.

The defense? We’ve been concerned about every aspect of this group for months (check our archives) and those worries were reinforced tonight, with Dallas piling up 300 yards and 27 points in the first half, scoring on five of their six possessions, then needing only two plays to march 59 yards for a touchdown to start the third quarter.

"It's tough when you get drummed like this - let's call it what it is," Adam Gase said. "[The run defense] surprises me a little bit, considering the amount of time we spend on tackling. We need to clean that up. We're doing the right thing in practice and reverting back when we get back on the field to being a little sloppy."

After three series --– against primarily Dolphins starters and a few backups --- Cowboys quarterbacks were 8 for 9 for 125 yards and a 115.8 passer rating, and the Dallas running game (primarily Alfred Morris) was averaging 7 yards per carry.

And oh yes, Dallas backup QB Dak Prescott had a perfect 158.3 passer rating (12-15-199 yards).

Dallas closed with 433 yards and averaged 5.0 yards per rushing attempt.

Nat Moore says “the defense was supposed to be the strength of this football team.”

Really? Why would he –-- or anybody –-- think that? What evidence of that was there was last season, or what about the offseason personnel moves suggested this group would be really good?

So we ask this again: What, specifically, is this defense going to be above average doing? They’re subpar against the run --- 28th last season and having added players who graded out well below average against the run last season (if you believe PFF, and we know some of you don’t).

Their pass defense is leaky, primarily because of a suspect group of cornerbacks. (Hopefully, Xavien Howard will be something of a panacea. But the kid is a rookie and mistakes are inevitable.)

The linebackers aren’t game-changers and historically, not particularly durable.

The Dolphins assume they will be well above average rushing the passer, and that could be the case. But against a high-quality Dallas offensive line (and with Cam Wake held out), the Dolphins didn’t get any sort of rush, finishing the night without a sack.

Breaking down the specific defensive miscues against the starters (and some backups) early on:

• There was a Tony Lippett pass interference against Dez Bryant before the Dolphins forced a punt, the only one they forced for hours.

“Lippett really struggled; he’s got to learn to locate the football,” team employee Nat Moore said late in tonight’s game broadcast.

• The second defensive series was a disaster, filled with breakdowns. Bryant beat Byron Maxwell for 18 yards, without a whiff of a pass rush. Jason Witten beat Kiko Alonso for 12 yards, with Alonso completely out of position.

Lippett was then out of position on a corner blitz, and Chris Jones was knocked away on a 13-yard run by Alfred Morris. Witten then beat Jelani Jenkins for another first down, with Jenkins missing the tackle. (Can’t wait to see Dion Jordan have a chance to defend big tight ends again.)

On Morris’ 15-yard touchdown run, Andre Branch missed a tackle, and Terrence Fede and Chris Jones were swallowed up. Not good.

• Prescott and the Cowboys did as they pleased on Dallas’ third series, with Isa Abdul-Quddus beaten for a 20-yard reception; Mario Williams embarrassingly whiffing on a tackle against Morris, which turned a play which should have been no gain into a 20-yard jaunt; Cole Beasley shaking free, completely uncovered in the slot, and then Bryant beating Maxwell for a touchdown.

• Later, on Prescott’s 20-yard TD run, Chris McCain was knocked to the ground while Prescott was still in the backfield, and Thomas, Fede and Lippett all failed to tackle Prescott as he sprinted to the end zone. That drive would have ended much earlier if an Abdul-Quddus pick hadn’t been negated by a roughing the passer penalty against Andre Branch, who didn’t have a good night.

• Then to start the second half, Brice Butler beat Bobby McCain for 58 yards on a terrific deep pass from Prescott, and then Butler beat Rashaan Melvin for a two-yard TD pass.

Other things:

• Pedestrian night for Jakeem Grant, who had 9 yards combined on two punt returns and 49 yards combined on two kickoff returns. Offensively, he didn't have a catch.

• Spencer Paysinger is serviceable and Neville Hewitt had some moments (including a blitz that forced a third-down incompletion), and Mike Hull had six tackles. But backup linebacker remains a question. James Michael Johnson looked lost on a screen pass, then whiffed on a tackle on special teams.

The Dolphins appear disinclined to spend much money on any free agent linebackers. They asked accomplished starter Steven Tulloch to work out a couple weeks ago, but Tulloch wasn’t interested because the Dolphins were only looking to sign linebackers to a very low-money deal. (They signed Danny Lansanah, who was gone less than a week later.)

Tulloch remains available, but the Dolphins haven’t shown interest in him (or apparently any linebacker) at the type of money he’s seeking.

• Arian Foster’s Dolphins debut was uneventful: 2 for minus 5 yards. Jay Ajayi ran 6 times for 19 yards, just 3.2 per carry.

The other backs: Isaiah Pead 4 for 48, Daniel Thomas 7 for 30 and Damien Williams 4 for 2.

• The Dolphins have put their tight ends on notice that more is expected, and Jordan Cameron disappointed by dropping a very catchable four-yard pass that should have been a touchdown. Three more plays (including incomplete passes to Landry and Kenny Stills) foiled that drive, but Tunsil was very good in pass protection on all three passes close to the goal line.

• Tunsil got snaps at left tackle and left guard in the second half, and had a terrific block on Pead’s 45-yard run.

• Matt Moore left late in the second quarter with a head injury on an illegal hit, meaning an earlier than planned appearance for Brandon Doughty.

Backup center Anthony Steen’s high snap was the first misstep in Doughty’s fumble late in the first half, leading to more Cowboys’ points.

Steen, surprisingly, has been ahead of Jamil Douglas and Kraig Urbik at backup center for the first two games.

Doughty, incidentally, was 2 for 3 for 7 yards before being lifted late in the third quarter. Zac Dysert (3-6-44 yards) finished the game.

• Rookie tight end Thomas Duarte, a skilled pass rusher not known for his blocking, whiffed on a block that led to Matt Darr’s blocked punt.

Dominique Jones, making a case for the No. 3 tight end job, had two catches for 36 yards but dropped a pass for the second week in a row.

• The Dolphins had four tackles for loss, only one by a player who might be on the team (Chris Jones).

• The Dolphins were 0-3 and outscored 94-45 last season in games televised to the entire nation. NFL Network witnessed this Dolphins drubbing tonight, and NBC nationwide get to see them against Atlanta on Thursday.

Twitter: @flasportsbuzz