SETTING THE SCENE: It was a hot one in Mankato as the Vikings opened training camp Sunday. Temperatures were in the mid-80s, but it felt even hotter with the sun beating down. The players were in helmets and shells during the afternoon practice. They won't be in full pads until Tuesday.

OFFENSE STARTS COLD: As is usually the case early in training camp, the defense looked better than the offense, mostly because the offense was so out of sync whenever the ball wasn't being handed to Adrian Peterson or a fellow back. Whether it was due to errant throws, collapsing pockets or miscommunication, a lot of passes hit the turf. Starting quarterback Teddy Bridgewater fared alright, but it wasn't pretty for the three other guys.

WALLACE WORKS HARD: New receiver Mike Wallace impressed with his work ethic during the first day of camp. He was relentless out there, going all-out to dive after low throws and at one point cussing himself out for not scooping one of them off the grass. And then he was the last man off the field again after his standard post-practice JUGS machine session. I know it's early in his tenure here, but he has been a tone-setter.

BABS' UNEVEN DAY: Big offensive tackle Babatunde Aiyegbusi produced inconsistent results in 11-on-11 work. He bulldozed rookie defensive end Danielle Hunter on one running play, but got beaten by Hunter in pass protection and had to tackle him to keep him away from the quarterback. Linebacker Josh Kaddu also beat Aiyegbusi wide once with a speed rush.

TWO-MAN BATTLE?: Fifth-round pick Stefon Diggs and incumbent punt returner Marcus Sherels handled the bulk of the punt-returning duties in practice. Adam Thielen and Jerick McKinnon, an intriguing option due to his athleticism, also got some work in back there. But it looks like Diggs has the best chance to unseat Sherels (good luck with that, kid).

A LEG UP … FOR NOW: Audie Cole ran ahead of second-round pick Eric Kendricks as camp opened, but the more versatile Kendricks is still the favorite to start at middle linebacker. Robert Blanton, meanwhile, was also with the first-team defense, as his usual spot next to Harrison Smith. Andrew Sendejo and Antone Exum were the second-string safeties.

CAMP CHATTER: "This is one of the hottest days it's been in four years here for me. … But there was a lot of energy." — wide receiver Jarius Wright.

INJURY REPORT: Cornerback Josh Robinson, who started camp on the PUP list due the pectoral he injured in June, said there is a chance he could be ready by Week 1, though he didn't say it with much confidence. Nose tackle Shamar Stephen and wide receiver DaVaris Daniels also sat out with injuries. Kaddu limped off near the end of practice.