During a portion of Friday's practice, six players knelt in a half circle around Colorado offensive coordinator Brian Lindgren.
Five were quarterbacks. The other was junior receiver Nelson Spruce.
"Nelson was just listening in," starting quarterback Sefo Liufau said. "We were just talking through plays and if we saw a certain coverage what we'd do, and protections and all of that."
Spruce didn't have to be there, Liufau said, but taking the time to sit in on that discussion is an example of the time and effort Spruce has put in to make himself as good as can be.
"He's very mature," receivers coach Troy Walters said. "He's come a long ways and he just keeps getting better each practice."
Ever since Paul Richardson made the decision to leave CU early and go to the NFL — he was selected by the Seattle Seahawks in the second round of the draft in May — fans have wondered how the Buffaloes are going to replace the star receiver.
Freshman Bryce Bobo is often viewed as a potential star. There are high hopes for other youngsters, too, such as Elijah Dunston, Devin Ross and Shay Fields.
What about Spruce? Could he potentially be the star receiver that replaces Richardson?
"Yeah, I think I can be the leading guy," Spruce said. "I'm not going to be able to do the same things down the field (as Richardson). He just had a different level of speed that is just freaky. Not one guy is going to replace Paul, but we're super deep this year and we're going to have more guys making plays as opposed to just one big playmaker."
The Buffs might be deeper at receiver than they've been, but there's no question Spruce will be a big part — if not the biggest part — of the passing game this season.
Through two seasons, he has 99 catches for 1,096 yards and seven touchdowns. He already ranks among the top 15 in CU history for catches and has a good chance of joining Scotty McKnight as the only Buffs with 200 catches; McKnight had 215.
A year ago, Richardson had 83 catches for 1,343 yards. Walters doesn't see those numbers as being untouchable for Spruce this year. Spruce had 55 catches for 650 yards last season.
"Production wise, number wise, I think Spruce can do what Paul did," Walters said. "He's a different type of receiver, but I think when it's all said and done, he has the ability to have over 1,000 yards, over 80 receptions. Other guys need to step up so that Nelson doesn't get double and triple teamed.
"I think he can be explosive. I think he can create yards after the catch. He's going to catch some deep balls. He's practicing well, so he's going to play well."
As a vital part of the passing game the past two years, Spruce has gained confidence and experience to take his game to another level, he said.
"I feel like now I know what Pac-12 football is all about, so right now it's just about mastering the little things," he said. "I'm really working on a lot of the details with coach Walters, working on my speed and being effective with the deep ball. It's something I think I can do to expand my role. I'm feeling confident, feeling good; my body is feeling good."
Spruce is also feeling more comfortable with Liufau, who took over the starting role midway through the 2013 season. Prior to that point, Spruce had spent countless hours working with former starter Connor Wood and didn't have as good of a rapport with Liufau. Now that duo is in sync.
"I kind of know when he's going to break on certain routes and what he's going to do when a (defensive back) does a certain thing," Liufau said. "This summer and even this spring gave us a lot more time to hone in our timing. I think we're on a better page than last year."
Liufau and Wood both leaned on Richardson last year. Spruce can be that same type of safety net, Liufau said.
"Spruce is not as fast as Paul, but I think he runs really good routes," Liufau said. "He keeps the DBs guessing. He's also a team leader out here."
Voted a team captain in the spring, Spruce is eager to see how much better the team, as a whole, can be this year.
"We're so far ahead of where we were at this point last year," said Spruce, who may also return punts. "We've built off a lot of the things we did well last year. I'm just super excited to get this season started."
A big year from Spruce will help the Buffs improve.
As for the question of who will replace Richardson, Spruce said he's just fine with everybody talking about Bobo and others.
"I don't mind flying under the radar and doing my thing," he said.