Colorado's most explosive player sat on the sidelines last fall stewing with a knee injury. He watched his teammates get stomped on a weekly basis. He heard the catcalls in the stands. He saw the smirks from opponents. It wasn't fun.

"Excruciating is a good word for it. It was pretty painful," Buffaloes receiver Paul Richardson said. "All I could think about last season was what I could have done or how I could have helped."

And Richardson knows exactly what people think of Colorado as the calendar flips into 2013.

"I expect nothing less than for people to sell us short or pick us to finish last," he said. "I even joked before in another interview that if there was a spot below last they'd pick us there as well. But you never know what will happen in the Pac-12."

That last part is true. Still, there is a high degree of confidence out there that Colorado will again inhabit the Pac-12 basement. Sure, it should be improved compared to 2012, but that's largely based on the belief the Buffaloes were one of the worst teams in conference history last fall. It feels like things can't get any worse. So there's that.

And yet ... maybe there's a little more than that.

The Buffaloes welcome back 18 starters from an absurdly young team. They played 22 freshmen, including 13 true freshmen last fall. Some teams played more, such as Texas, LSU and Ohio State, but those teams are recruiting different sorts of players, elite prospects with no assembly required. Colorado was forced to play guys who were not physically ready for Pac-12 play. And it showed.

At the very least, they will be more ready this year. If the Buffs get a breakthrough at quarterback -- redshirt freshman Shane Dillon, a former Elite 11 quarterback? Incoming freshman Sefo Liufau? -- Richardson is a game-changer with the ball in his hands, just ask California, which yielded a school-record 284 yards receiving to him in 2011.

While many only see the mess that former coach Jon Embree presided over, Richardson sees the potential improvement new coach Mike MacIntyre inherited.

"I don't think Coach MacIntyre is in a bad position at all," he said. "I think he was given an opportunity to move up to this coaching job at a really good time. We're going to have some key players back and our young guys are going to have experience. To me, he came at a perfect time."

Embree, who was fired after just two seasons, is a sore subject for many Buffs, including Richardson. While the team is going through spring practices preaching optimism and looking forward, looking back still evokes grumbles.

"I was very upset to say the least [at Embree's firing]," Richardson said. "It was very surprising. I had a really good relationship with coach Embree. It caught us all off guard. Some of us were pretty bitter."

He then adds, "But we've grown from that. I miss Coach Embree. I miss [offensive coordinator Eric Bieniemy]. I miss the staff. But all we can do is go forward. We've got to turn this program around and start winning some football games."

A 6-foot-1, 170-pound junior from Los Angeles, Richardson was second on the team in receiving yards (514) and touchdowns (6) as a true freshman in 2010. He looked like a potential All-Pac-12 performer in 2011 before a knee injury sidelined him for four games. His 2012 hopes were dashed when he tore his ACL the final week of spring practices.

The only question with Richardson, who has good speed and reliable hands, is health.

"I feel incredible," he said. "I know I'm more explosive than I was before. I know I'm faster than I was before. I'm more mature. I'm stronger. I'm a better leader. Conceptually, I'm grasping the offense and I'm able to pull guys along with me."

Asked if his "pulling guys along" includes figuring out who will be throwing him the ball, Richardson is noncommittal. It's too early to make a call at quarterback, though MacIntyre has said he plans to narrow the competition to three guys before spring practices hit the half-way mark on March 22.

"It's a healthy competition," he said. "There are kids people expect to start, but every day somebody is showing something different. I can't tell you who is winning the race."

Richardson's career has been star-crossed thus far. But if his luck changes, so might the Buffs' fortunes.

"I think we'll be .500 or above," he said. "The best thing I can say is don't sleep on Colorado football. We're a work in progress, but it is progressing over here."