The Vikings added Cordarrelle Patterson with the 29th overall pick in the NFL draft and signed free agent Greg Jennings to strengthen the wide receiving corps after losing Percy Harvin to Seattle.

But there might be a surprise addition in free agent receiver Adam Thielen from Minnesota State Mankato. Vikings coaches first observed him while in training camp in Mankato. They brought Thielen to free-agent/rookie camp earlier this month and he was impressive enough to sign.

"Adam Thielen has done a good job for us," wide receivers coach George Stewart said. "… I saw him a couple years ago — of course they practice on the same field we do in training camp — and I saw the young man kept improving, improving and we had a chance to sign him to a contract. We're looking to see good things out of him."

Thielen said he wasn't surprised to be one of two rookies (out of 34 trying out) to be signed out of the free agent camp. The other was Brandon Keith, an offensive tackle from Northern Iowa who was out of football last year after starting for Arizona in 2011.

"I thought that I had a pretty good rookie camp and had a lot of fun here," Thielen said. "I was hoping they'd sign me, but I wouldn't say I was necessarily shocked. Growing up from Minnesota, I definitely was a Vikings fan. I've always liked Minnesota."

Thielen started three years at MSU Mankato after playing some as a freshman. The 6-3, 200-pounder, who was timed in a speedy 4.45 seconds in the 40-yard dash at the NFL combine, caught 74 passes for 1,176 yards to help the Mavericks to a 13-1 record and into the NCAA Division II semifinals last season. He is second in MSU Mankato history in receptions (192) and receiving yards (2,674) and third in touchdown catches (19).

He was invited to the Carolina Panthers training camp as well as the Vikings.

"I definitely wanted to get signed here, and I'm just happy they liked me," Thielen said. "Absolutely it gave me a little bit of confidence, that's for sure."

Likes Patterson

Stewart also had high praise for Patterson after working with him for a short time.

"Cordarrelle Patterson has done a super job," Stewart said. "Coming in from [the University of] Tennessee, he has really, really caught on to what we're trying to get done. [Vikings General Manager] Rick Spielman and his staff did an outstanding job of moving back up [in the draft] to get him. He's going to be a very productive player for us.

"He has speed, he has ability to separate, to jump for the football. We think he's a guy that's going to help us in the red zone as well as our [overall] passing game. He's done a great job leading, doing a great job in terms of picking up what we're trying to do scheme-wise."

Stewart is thankful to have Jennings, the former Green Bay Packers star who Atlanta almost drafted when Stewart was on the Falcons staff.

"He's a guy that we thought we may draft in Atlanta," Stewart said. "We ended up drafting Roddy White [No. 27 in the 2005 draft]. We thought we might have a chance to go get [Jennings] in the second round [in the 2006 draft], and he was already taken by Green Bay. So it's an opportunity for me to get a second chance to coach him.

"We have a deep group, a lot of talent. It's a great situation for us to be in."

High on Hageman

CBSSports.com recently praised Gophers defensive tackle Ra'Shede Hageman, ranking him No. 2 on Bruce Feldman's "Freaks" list of defensive players to watch in 2013. Gophers football coach Jerry Kill agrees that Hageman has a great future.

"Brandon Jacobs was a young man who played for me at Southern Illinois who was a freak of nature," Kill said of the former New York Giants star. "There weren't any running backs running around who were 6-5 and 265. That's just unusual.

"Ra'Shede's body type is 6-6, 315-320 [and he can do a 360-degree] dunk. There's not many people like that."

Kill said Hageman, who was originally recruited as a tight end, still is learning his new position with the help of defensive coordinator Tracy Claeys and defensive line coach Jeff Phelps.

"Coach Phelps and Coach Claeys have both done a great job with him. Also, from an academic side, our academic staff has done a great job with Ra'Shede. He's working hard. Those are the types of players that when you line up against the best in the country, you've got to line up with people just like that. I've always said we need four or five like that on offense and four or five like that on defense. Then you can go ahead and compete, there's no question about that."

Jottings

• The only Vikings player missing from the OTA on Wednesday was defensive end Jared Allen, who has his own conditioning program.

• One of the Twins' more positive additions has been reliever Jared Burton, who was signed as a free agent in 2012. Going into Wednesday's game with the Brewers, he had a 2.19 ERA in 24 ⅔ innings this season. "Burton has been good ever since he came over here, he's just a dependable guy," Twins General Manager Terry Ryan said. "He challenges hitters, throws a lot of strikes, he can strike people out, and he's good against lefties or righties. It's comfortable to have [Glen] Perkins and Burton in the backside of that bullpen. I think it sets everything up for the other relievers. He came over and he had a lot of injury history with him. He's stayed healthy here, and it has certainly worked out for both of us."

• Flip Saunders, the Timberwolves' new president of basketball operations, continues to travel and spend time with the players. This weekend Saunders will be in Miami talking basketball with point guard Ricky Rubio. … Saunders reported that forward Derrick Williams' recent jaw surgery was a complete success.

• Gophers athletic director Norwood Teague was asked if there is any more talk of further expansion in the Big Ten. "I do think expansion is done for the time being. It seems that way, especially with the ACC having the rights signed from all the schools."

• Ben Revere, who hit .294 with 32 RBI and 70 runs scored last year for the Twins, is hitting .263 with five RBI and 17 runs scored in 46 games so far this season playing center field with the Phillies.

• Twins catcher Joe Mauer recently talked about what it's like to hit at Boston's Fenway Park: "That's a great place to hit. Your approach is a lot different, you know a lot of balls that you hit to left, even if you mishit it, are doubles instead of outs. It's a great place to hit, a great place to play with all the history and the players that have come before you there. They have a great atmosphere there."

Sid Hartman can be heard weekdays on 830-AM at 6:40, 7:40 and 8:40 a.m. and on Sundays at 9:30 a.m. shartman@startribune.com