All in all, most observers would say Virginia quarterback Michael Rocco had a successful debut as the Cavaliers’ starter. He didn’t wow anyone, but he wasn’t asked to. In fact, he did just about everything he was asked to do.

Rocco completed his first 11 passes Saturday against William & Mary, though few of them spent much time in the air. Coach Mike London and Offensive Coordinator Bill Lazor said afterward they wanted Rocco to get into a rhythm, especially at the outset of the game. Most of Rocco’s throws were short, and check-downs were a commonly sought.

Rocco’s final stat line: 21 of 29 passing for 174 yards.

“I think Michael did a great job taking what was given to him with the mind-set of not trying to ask him to do too much and then executing,” London said Monday. “Now we go into Game Two, and will we throw the ball downfield more? Perhaps. Every team presents a different challenge.”

We’ll delve into Virginia’s next opponent, Indiana, later this week. But for now, let’s try a different method for evaluating Rocco’s performance Saturday.

Last spring, I read about a formula that East Carolina Offensive Coordinator Lincoln Riley uses to judge his team’s quarterbacks. The formula seemed sensible and easy enough to understand, and so I’m going to apply it to Rocco’s outing. Perhaps we’ll make this into a weekly thing after each game.

The formula attempts to measure how effective a quarterback is in moving his team down the field. Riley’s belief – according to an interview he did with’s Bruce Feldman – is that quarterbacks should be gauged based on their percentage of “bad plays.”

“Every QB out there is capable of good plays,” Riley told Feldman. “But it’s about what you do when you can get those bad plays. They have to be minimized by, say, throwing the hot route off the blitz and getting two yards or throwing the ball away and not taking the sack. If those are our bad plays, we’re going to win.”

Riley qualifies a bad play as a sack, an interception, a turnover, one that results in negative yardage or one that results in an offensive penalty. The quarterback is only responsible for the plays during which he is on the field. According to Riley, a quarterback’s percentage of bad plays needs to be less than 15 percent to win games, though less than 12 percent is ideal.

On Saturday, Rocco was on the field for 58 snaps. The Cavaliers tallied six “bad plays” under Rocco’s watch, which comes out to 10.3 percent.

Riley told Feldman that good plays are pass plays that gain at least 15 yards, run plays that gain at least 12 yards, plays that result in touchdowns or plays that result in first downs.

Against William & Mary, Rocco was on the field for 18 “good plays,” which equates to 31 percent.

Rocco said Monday that Lazor emphasizes “making sure every play is a positive play,” a strategy that includes hitting check-downs if passing options downfield are not open.

Rocco’s ability to notch percentages of what Riley identifies as good and bad plays similar to the rates he posted Saturday may go a long way toward determining how often Virginia is in position to win games this season.