The line between acceptable improvement and another disaster of a season was blurred on back-to-back Saturdays this fall.

Michigan collapsed at the first sign of adversity Halloween afternoon against Illinois, and a week later melted down in the span of 9 seconds against Purdue.

Had the Wolverines won either game, they’d be bound for a bowl somewhere warm, not left to pick up the pieces of their second losing season in 42 years.

“It’d be nice to go to a bowl game, but that’s not our ultimate goal,” Michigan coach Rich Rodriguez said. “Our ultimate goal is to win a Big Ten championship. Short of that, you can maybe be a little happier but you’re not going to be fulfilled for sure.”

Michigan made strides from last year’s 3-9 season. The Wolverines won two more games with an at-times potent offense, underclassmen Tate Forcier, Roy Roundtree and Craig Roh look like viable building blocks, and Rodriguez said team chemistry, fortified by a slew of off-field distractions, was as strong as its ever been.

But the Wolverines still appear to be a world away from contending, and minus 15 extra bowl practices, there’s reasonable doubt they’ll get there under Rodriguez.

The second-year coach has drawn fire for his record (8-16 overall and 3-13 in the mediocre Big Ten), his treatment of players (an NCAA investigation into excessive practice time should wrap up next month) and, of course, his pedigree (he’s not a Michigan man).

Some of the criticism is fair, some unfounded, and Rodriguez alluded to factions working against the program after Michigan’s season-ending 21-10 loss to Ohio State, its sixth straight in the rivalry series.

“Just let us do our job and we’ll be OK,” Rodriguez said.

Maybe, but things aren’t that simple.

Rodriguez said recruiting shortfalls “the last 3 Februaries or 4 Februaries have hurt us a little bit,” and “the next 2 or 3” recruiting classes will be critical to building the program.

Of course, with a new athletic director slated to start sometime next year and bad news piling up like laundry - the latest, the arrest of an unidentified freshman for alleged criminal sexual contact over the weekend - Rodriguez doesn’t have 3 recruiting classes to get things right.

Michigan needs to show significant improvement next fall or he’ll likely be shown the door.

Outgoing AD Bill Martin gave Rodriguez another hollow vote of support Saturday, but the only voice that matters, president Mary Sue Coleman has been strangely silent of late. For the sake of a recruiting class so essential to the program, she needs to speak out this week and put questions about Rodriguez’s immediate future to rest.

Rodriguez did his best to move forward Saturday, saying he’s identified most of the problems that ail his team and he’s sticking with the same blueprint he used to turn West Virginia into a national power.

“We’re going through a growing process that we’re not accustomed to here at the University of Michigan,” Rodriguez said. “I’m not accustomed to it either. But I’ve been through it before and we’ll get it done.”

Notes, quotes and leftovers • Turnovers aside, the biggest sequence of events Saturday came in the span of three plays on Ohio State’s third-quarter touchdown drive.

Brandon Graham almost kept the Buckeyes out of the end zone singlehandedly. On first-and-goal from the 2, coming off his left end position in a five-man front, he knifed inside tight end Jake Stoneburner to drop running back Dan Herron for a 2-yard loss.

On second-and-goal, Graham held his ground on a play fake and another juke move by quarterback Terrelle Pryor and sacked Pryor for an 8-yard loss.

On third down, just as Michigan, trailing 14-10, looked like it might hold the Buckeyes to a field goal, OSU dialed up a timely screen pass against an all-out blitz. Jordan Kovacs rushed Pryor from his safety position leaving the middle of the field open, and Pryor lobbed a 12-yard touchdown pass to Herron over Ryan Van Bergen.

“They just called a perfect call cause we had a blitz going and then they had a screen,” safety Troy Woolfolk said. “It wasn’t a matter of people being out of line or making mistakes like in the past. Everybody executed the play, they just got lucky. It is what it is.”

• Graham finished with four tackles for loss, giving him an NCAA-best 25 on the year. Just three other players - Army’s Josh McNary (22 1/2), UCLA’s Brian Price and Wisconsin’s O’Brien Schofield (20 1/2 each) - have more than 20, and each has one game to play.

People don’t realize how good a season Graham had. With two blocked kicks, two forced fumbles and 9 1/2 sacks (I still contend he should have had 10), Graham would be an All-American if he played on a better team.

• Forcier had five costly turnovers, but with no viable backup quarterback it’s hard to fault Rodriguez for not benching him earlier (and it’s still puzzling why he didn’t give Forcier a chance to win the game at Iowa).

Denard Robinson played 15 snaps at quarterback Saturday. Of his first 11, 10 were designed runs. When he was finally asked to pass four times on Michigan’s final drive, Robinson threw a screen pass complete but behind Mike Shaw; grounded a ball in the direction of Junior Hemingway; took a sack when he stepped into pressure despite an open receiver to his right; and panicked on a fourth-down incompletion, throwing the ball to a patch of grass when no receiver was within 20 yards.

Robinson finished the season with 69 carries for 351 yards and completed 14-of-31 passes for 188 yards with two touchdowns and four interceptions.

• Robinson didn’t talk with reporters Saturday, but freshman Vincent Smith said he expects his classmate to return and compete for the starting job next year.

“He’s very patient and he stays positive and he knows when his number’s called he needs to step up to get the job done,” Smith said.

• Brandon Minor led Michigan in rushing for the second straight year. His 502 yards was the lowest total by a rushing leader since Mel Anthony’s 394 yards in 1963.

Dave Birkett covers University of Michigan football for AnnArbor.com. He can be reached by phone at 734-623-2552 or by e-mail at davidbirkett@annarbor.com. Follow him on Twitter @davebirkett.