In the Vikings' first preseason game, Roc Thomas stole the show with a pair of receiving touchdowns, including a 76-yard score off a screen pass that highlighted the rookie free agent's versatility as an option to help replace Jerick McKinnon in the Vikings' offense.

On Saturday, it was Mike Boone's turn. The Cincinnati product gained 91 yards on 13 carries, including a 26-yard burst that turned out to be the Vikings' longest play of the day. And a week after allowing a sack when he reacted late to a blitz up the middle, Boone appeared to take a step forward in pass protection in the Vikings' 14-10 loss to the Jaguars.

"Mike stepped up on that last drive on the fourth down and blocked the defensive end," quarterback Kirk Cousins said. "You could hear the pads pop; he displaced the guy and gave Kyle a chance to step up and make the throw. It's stuff like that too, with a trained eye, you love to see from a young running back."

And so the Vikings' competition for the third running back spot is on, with Thomas chipping in another 37 yards from scrimmage on Saturday. The Vikings will likely give their starters more playing time on Friday night against Seattle — and while coach Mike Zimmer continued to play coy after the game about using Dalvin Cook in the preseason, it stands to reason the Vikings would do so Friday night if they decide to use the running back before the regular-season opener.

That might leave fewer opportunities for Boone and Thomas against the Seahawks, but they'd have plenty in the preseason finale on Aug. 30 in Tennessee. The running back competition figures to remain close until then.

"That's what we come here to do: to compete, to make plays," Boone said. "That's the goal every game — not just because Roc played well in that game [against Denver]. I try to come every game and put my best foot forward."

Here are some other quick-hit thoughts after the Vikings' second preseason game:

Busy day for Aviante Collins: The second-year tackle started on the right side in place of Rashod Hill on Saturday, playing ahead of second-round pick Brian O'Neill. "I just thought he had a better week," coach Mike Zimmer said. "He battled all week long, I thought he had a better week. Aviante is a very good athlete, got good strength and size to him. The way they were rushing some of the guys, some of the power rushes, I felt like he would be better." Collins shifted to left tackle after Riley Reiff came out of the game with the rest of the Vikings' established starters, then moved to left guard after injuries forced the Vikings to shuffle the group further. In total, he played 49 snaps, more than any other offensive player. The Vikings kept Collins on their 53-man roster last year, and he'd seem like a good bet to make the team again.

Vikings keep moving Hughes: First-round pick Mike Hughes got some work with the Vikings' top nickel defense after Mackensie Alexander left with an ankle injury in the first quarter, and the Vikings followed by playing Hughes for a few snaps at left cornerback with their top base defense. Before Alexander was injured Saturday, the Vikings returned to a similar plan at the nickel spot to the one they used last year, playing Terence Newman when they were in nickel in potential running situations and bringing Alexander in on obvious passing downs. Hughes took that role after Alexander left, and the fact the Vikings gave him some work at Trae Waynes' normal spot is another step in the indoctrination process for a rookie who continues to be impressive. X-rays came back clean on Alexander's ankle on Saturday, according to a league source; he will have a MRI on Sunday. But even if he avoided a serious ankle sprain, the Vikings know they can never have too much cornerback depth, and Hughes being ready to go in Year 1 would be a big help.

Run game continues to succeed: Before Latavius Murray's first fumble on Saturday, the running back burst through a big hole on the left side of the Vikings' line for a 13-yard gain. That turned out to be the most explosive play the Vikings' first-team offense generated in five series of work, and while Murray's two fumbles are notable for a back who fumbled just once last year, he's continued to find room on downhill runs after breaking two for 20 yards or more against Denver. "We've run the ball well, I think, in the first two preseason games and really throughout all of training camp," Cousins said. "I've been really pleased with how we've run the football."

Beebe shines late again: A week after catching a fourth-quarter touchdown from Kyle Sloter on a corner route, wide receiver Chad Beebe made another late play that put the Vikings in position to take the lead. Sloter found the rookie for 14 yards after Beebe beat his man on a crossing route, giving the Vikings 1st-and-10 at the Jaguars' 22 with 55 seconds left. The diminutive rookie still might be a long shot to make the Vikings' roster, but he's impressed with his crisp route-running skills and fluid movement throughout training camp, and could stick as a practice-squad player.