The cleats best-suited for digging into a wet or soft field aren't necessarily the best option for an artificial surface. That's why shoes or cleats can be changed from game to game. Still, success ultimately isn't a matter of the shoes, but rather the players who wear them.
With that in mind, the rosters of several teams are like the closet of a large-footed woman - there are a lot of big shoes to fill.
That's an annual occurrence in college football. Players complete eligibility, depart early for the NFL or get injured or suspended. Those departures often leave teams having to replace All-Americans with unproven backups or prospects.
Those replacements are more precarious for some teams than others. For example, LSU is without All-America guard Herman Johnson, but the Tigers still project to be better than last season's eight-win team.
Some teams that won or contended for championships last season but relied heavily on individuals who are gone will face big questions and the possibility of dramatic declines.
In 2004, Ole Miss replaced Eli Manning - who threw for 3,600 yards the previous season - with Ethan Flatt. Flatt passed for 1,530 yards with more interceptions than touchdowns, and the Rebels' victory total dropped from 10 to four.
Sometimes, though, a new starter proves better than his predecessor. Oklahoma State's Thurman Thomas was replaced by Barry Sanders, who in 1988 had the best season for a running back in NCAA history.
Here's a list of some of the biggest shoes to be filled this season. How adequately they are filled may determine the outcome of a team's season.
Texas Tech WR Michael Crabtree, by Detron Lewis: Lewis caught 76 passes for 913 yards last season, which would indicate he has some talent. But this season, Lewis ascends to the role as the Red Raiders' No. 1 target, a distinction held the past two seasons by Crabtree. A two-time All-America selection, Crabtree caught 231 passes and scored 41 touchdowns in his brief career. More important, he led Texas Tech's rise from solid program to championship contender. Lewis may find getting open more difficult without Crabtree drawing double coverage and occupying opponents' best defensive backs.
Missouri QB Chase Daniel, by Blaine Gabbert: All Gabbert has to do is step in for the most successful quarterback in Missouri history. The Tigers were 30-11 with two appearances in the Big 12 championship game and two bowl victories with Daniel as the starter. Daniel also left Missouri with several school records, including career total offense. Gabbert, a sophomore, hasn't thrown a college touchdown pass. But take heart, Mizzou fans: Daniel took over for Brad Smith, who at the time was considered the best quarterback in school history. Maybe history will repeat itself.
Iowa RB Shonn Greene, by Jewel Hampton: Last season, Hampton showed a lot of promise when he rushed for 463 yards and seven touchdowns as a backup as a true freshman. But all that production was gravy. Now, he has to replace Greene, who was the meat and potatoes of the Hawkeyes' offense in '08. Greene rushed for 1,850 yards - the second-highest total in the nation - and scored 20 touchdowns. His power running also helped the Hawkeyes control the ball, which gave the defense a boost and was a major factor in Iowa posting nine wins. Hampton is more elusive than Greene, but can he be as productive?
Utah QB Brian Johnson, by Terrance Cain, Corbin Louks or Jordan Wynn: That trio will continue to compete for the Utes' starting quarterback job throughout August and perhaps into the season. Johnson threw for almost 3,000 yards last season. And while it's a cliché that quarterbacks get too much credit when their teams win, Johnson deserved a ton of credit for the Utes' undefeated season in '08. He made big plays to lead winning last-minute drives against Oregon State and TCU, then threw three touchdown passes in a Sugar Bowl upset of Alabama. Louks threw seven passes last season, when Cain was in junior college and Wynn was in high school. They need to come close to matching Johnson's stats, and they also must show some intangibles and leadership. And don't forget the second part of that cliché - quarterbacks get too much blame when their teams lose, so those guys better have thick skin.
Ohio State LB James Laurinaitis, by Austin Spitler: Spitler, a senior, has 44 career tackles - or about a third of the amount Laurinaitis made last season. Laurinaitis was an All-America who led the Buckeyes in tackles in each of the past three seasons and won the Butkus and Lombardi awards.
Ole Miss OT Michael Oher, by Bradley Sowell: Last season, the 310-pound Sowell split his time between tight end and tackle. This season, he'll try to fill the gaping hole at left tackle left by Oher's departure. Oher earned some All-America honors for his play in protecting quarterback Jevan Snead's blindside last season. Snead's effectiveness is at least partially dependent on Sowell's performance. If Sowell struggles, five-star recruit Bobby Massie could step in. But that won't change the enormous task of replacing Oher.
Texas DE Brian Orakpo, by Sam Acho: Last season, Texas led the nation with 47 sacks. The biggest reason was Orakpo, who had 11.5 of them. When Orakpo didn't get to the quarterback, his presence helped teammates get there. Acho, a junior who had three sacks in '08, likely will take Orakpo's place in the lineup. He doesn't necessarily have to match Orakpo's totals, but he does have to be an effective complement for Sergio Kindle. If Acho or another end isn't able to apply consistent pressure, Texas' defense may be considerably weakened.
USC QB Mark Sanchez, by Aaron Corp: Had Sanchez not opted to enter the NFL draft (he was the fifth player selected), the Trojans would have a proven quarterback and a Heisman contender. Instead, they have Corp, a sophomore who threw just four passes last season. Corp demonstrated a keen understanding of the offense and made great decisions to win the job during the spring. It will take more than sound decision-making to replace Sanchez, who threw for more than 3,200 yards and 34 touchdowns in '08. Corp doesn't have Sanchez's arm strength or big-play ability, but he is more mobile. The Trojans are overhauling their defense, so the offense needs to be sharp.
Alabama OT Andre Smith, by James Carpenter: Last week, Alabama coach Nick Saban said that in spring practice, Carpenter - a junior college transfer who enrolled in January - demonstrated he could "at least be a functional lineman." Under normal circumstances, that would be fine. But Carpenter is trying to replace Smith, an All-America who was perhaps the best offensive lineman in the nation last season. That leaves a high standard to meet for a "functional lineman."
West Virginia QB Pat White, by Jarrett Brown: Replacing a successful player is never easy. Following a legend who might have been the best player in school history might be a no-win situation. White was 34-8 in four years as a starting quarterback, won four bowl games, accumulated 10,529 total yards and accounted for 103 TDs in his career. White was named first-team All-Big East three times. Brown, a senior, made a few starts when White was injured, but he has thrown for just 839 yards and five touchdowns in his career. He is mobile, but he doesn't have nearly the acceleration that White had.
Olin Buchanan is a senior college football writer for Rivals.com. He can be reached at firstname.lastname@example.org.