No surprise: Rookies once again dominated the Seahawks’ preseason opener.

Last year it was draft picks Tyler Lockett and Frank Clark. This year it was undrafted rookies Trevone Boykin, Tanner McEvoy and Tyvis Powell.

After Boykin had left the game in the third quarter, he came back in the fourth and rallied the Seahawks to a 17-16 win in Kansas City with no time left. His 37-yard scoring pass to the 6-foot-6 McEvoy set up fellow UDFA Troymaine Pope’s winning two-point run.

It made Boykin and McEvoy the big standouts in Seattle’s first preseason game, along with Powell, pass rushers Cassius Marsh and Frank Clark, running back Christine Michael and the starting offensive line.

Michael and the line got off to a good start. The rededicated back gained 44 yards on seven carries, helping put the Hawks in position to score early — although Russell Wilson ended his only drive with an interception in the end zone.

Wilson had time to throw and Michael had room to run — a nice first effort by linemen (left to right) Bradley Sowell, Mark Glowinski, Justin Britt, Germain Ifedi and Garry Gilliam. The only glaring error was a bad hold by Ifedi on an outside keeper run by Boykin.

“I thought the first group did a great job driving the ball,” Pete Carroll said. “Christine looked good. The O-line was clean. … We looked solid. That’s a very good first outing for our guys.”

The defense had problems against Alex Smith and the Chiefs on the first drive. Missing Michael Bennett, whom Carroll said had been sick Friday night and Saturday morning, the defense let Smith and former Hawk Spencer Ware drive 51 yards, ending in Ware’s 1-yard touchdown run.

The Seahawks used a lot of personnel on that drive. Rookies Jarran Reed and Quinton Jefferson started, and undrafted rookie Brandin Bryant played a lot as well.

The standouts up front throughout the game, though, were Cassius Marsh and Frank Clark. Marsh looked good as a rusher, getting pressure several times and finishing with four tackles.

Clark showed some good moves and constantly pressured the Chiefs’ second unit as well. He drew a tripping call on one play in the second half. He also was called for unnecessary roughness on one QB hit at end of first half, but he showed great aggression nonetheless.

Before Boykin reclaimed the starring role, Powell had taken over. Early in the game, he sprung Lockett for a 17-yard punt return. He also made a tackle at the 10-yard line and almost downed a punt at the goal line (he stepped on the line).

The big special-teams day helped his cause for making the roster, and then he sealed it with an interception in the fourth quarter. He played both safety and cornerback, and Carroll said they are bringing him along as they did DeShawn Shead “back in the day.” (Shead had a nice day at corner, too.)

While the defense and special teams kept the Hawks in the game, it didn’t look like Seattle was going to put together enough offense to rally from a 10-point deficit.

While he was inaccurate and a bit jittery for much of the game, Boykin was at his best in the up-tempo offense — both at the end of the first half and at the end of the game.

Boykin came back to start the third quarter and led the Hawks to a field goal, cutting the deficit to 13-6. Jake Heaps came in for the next two drives, yielding nothing, and then Boykin was back for the fourth quarter.

It was an unorthodox move, but Carroll said the coaches had planned it that way. The offense went three-and-out on Boykin’s first drive in the quarter, but the rookie led them to 11 points on the final two.

The final drive started with just 1:07 left, and Boykin hit Montario Hunter for 18 yards, McEvoy for 32, E.Z. Nwachukwu for 1 and McEvoy for the 37-yard Hail Mary. McEvoy merely posted up against the much smaller defensive back — something Boykin said they have been telling McEvoy in practice. “Just box out,” Boykin said.

“It’s really nice to have a chance to win a game like that,” Carroll said. “There will be games all year long that will come down to the wire.’

Boykin said, “We preach it all the time. You play until the clock goes down to zero. And we did it today and came out with the win.”

OTHER OBSERVATIONS

**Alex Collins played sparingly but brought some Beast Mode spirit, pushing a defender 5 yards downfield after Collins made a catch.

**Brandon Browner made a great third-down stop in the hole, showing up in his new role as a line of scrimmage safety. He also rushed the passer.

**Carroll praised the kicking of Steven Hauschka (field goals from 52, 49 and 50 yards) and Jon Ryan, who boomed two punts over 60 yards and put three of his five kicks inside the 20.

**Tharold Simon did not look very good. He got called for pass interference after stumbling trying to cover Rod Streeter and also missed an interception.

**Stanley Jean-Baptiste suffered a shoulder injury.