AP

Johnny Manziel’s case of dehydration got most of the attention at last weekend’s Manning Passing Academy. But while Manziel was leaving early, North Carolina quarterback Bryn Renner was impressing people with his on-field performance.

The Manning Passing Academy is a high school football camp, but it also functions as something of an early pro day for college quarterbacks, who take the field for passing drills that give NFL personnel people an early impression of their passing skills. And Renner showed off a particularly good arm, according to Mike Mayock of NFL Network.

“As far as the quarterbacks, the seniors, Bryn Renner from North Carolina, I thought he probably was the most polished of all the quarterbacks I saw,” Mayock said. “Great feet, bigger kid than I thought — 6-3, 220 — ball comes out beautifully.”

Mayock noted that Renner’s dad, former Packers punter Bill Renner, is respected as a coach of young players, and Renner looks like he’s been well coached for years.

“His father is a highly recognized high school coach, so it doesn’t surprise me that he’s so polished,” Mayock said.

It shouldn’t surprise anyone if Renner — who completed 65.4 percent of his passes and threw 28 touchdowns and seven interceptions last season — is a first-round pick in the 2014 NFL draft.