Like he did three years ago when he nabbed Colin Kaepernick in the second round, San Francisco 49ers’ coach Jim Harbaugh is spending a portion of this offseason working out quarterback draft prospects.

The odds are the 49ers will use one of their 11 draft picks, likely in the mid rounds, on a quarterback to groom as a backup behind Kaepernick. Harbaugh has already personally worked out Virginia Tech’s Logan Thomas and Eastern Illinois’ Jimmy Garoppolo. He has upcoming workouts with Fresno Sate’s Derek Carr (who will likely be taken earlier than the 49ers want to take a quarterback) and San Jose State’s David Fales.

Harbaugh indicted he could work out more quarterbacks prior to the May 8-10 draft. Harbaugh, who was a quarterback in the NFL for 14 years, likes to play catch with the prospect during his private workouts.

“(I want to) see how he throws the football, more how they throw than the look in their eye,” Harbaugh said. “You’re always sizing somebody up as a player and so I kind of just use that in coaching as well to evaluate guys, try to size them up.”

He said the private workouts are an invaluable way to access a quarterback.

“Like to play catch with them. Like to see them throw,” Harbaugh said. "Go through their workout, see what kind of condition they’re in, and meet with them, talk to them. Talk football with them, protections. Try to get a feel for how much they know football-wise. Basically just talking football. Things you can’t do from watching the tape of a pro day.”