But Williams' recovery from that miscue, and the way he bounced back from a severe hit against Utah in the third game that caused a concussion, some scary moments on the field and an overnight stay in the hospital, has been remarkable.
Sophomore slump? Not a chance.
In Friday's Fight Hunger Bowl at San Francisco's AT&T Park, Washington's Bishop Sankey will deservedly get the lion's share of attention. After all, Sankey is the third-leading rusher in the country, averaging 147.9 yards per game. He rushed for 1,775 yards, breaking the school record for a single season.
But Williams put together a great season as well, despite missing most of the second half of the Utah game and all of the Middle Tennessee State game. He had just 14 carries in BYU's fifth game, against Utah State, as coaches eased him back. into the lineup.
The injury probably didn't keep him from reaching his goal of 1,500 yards, but it certainly didn't help.
"I just try to play my game and just admire other running backs and how they do it," Williams said of the comparisons to Sankey that will come Friday. "He's a great running back who goes out there and runs hard and does what he does best. I am just going to go out there and do me and not worry about what other running backs do."
The 6-foot, 200-pounder from Fontana, Calif., rushed for 1,202 yards, the sixth-best single-season total in school history, with one game left to play. And he did it in a year when another BYU player, Hill, rushed for 1,211 yards. They became the first duo at BYU to rush for more than 1,000 yards each in a season.
"I am a little surprised that I rushed for as many yards as I did," Hill said. "I am not surprised that Jamaal rushed for that. … He has had a really good season."
Halfway through his career unless he leaves early to chase his lifelong dream of playing in the NFL Williams already ranks 10th on BYU's career rushing yardage list, with 1,977. He needs 64 in the bowl game to pass Ronney Jenkins for ninth.
Harvey Unga's 3,455 yards is the standard, meaning Williams is on track to easily become the most prolific back ever at BYU, if he stays healthy and stays around.
He's not satisfied, however. Williams said he would give himself a B or a B+ grade this season. During fall camp, he talked about becoming a better blocker. Offensive coordinator Robert Anae said he accomplished the goal, and also became a better pass-catcher, with 18 grabs for 125 yards.
"Yeah, blocking is second nature now," Williams said. "I enjoy it now and I am getting better all the time. … I have no problem with blocking any more. I haven't perfected it, but I got more comfortable with it, and now it is one of my hobbies."
• Ran for a career-high 219 yards in 28-23 win over Nevada.
• FBS Independent Offensive Player of the Week against Idaho State, Nevada.
• Combined with QB Taysom Hill to become first BYU duo to rush for more than 1,000 yards each.
• Rushed for 1,202 yards and seven touchdowns, giving him 1,977 career yards and 19 touchdowns.
Best BYU rushing seasons
Player Season Yards
Luke Stale 2001 1,582
Pete Van Valkenburg 1972 1,386
Ronney Jenkins 1998 1,307
Harvey Unga 2007 1,227
Taysom Hill 2013 1,211
Jamaal Williams 2013 1,202
Fight Hunger Bowl
O BYU vs. Washington
Friday, 7:30 p.m.
TV • ESPN