KANSAS CITY, Mo. -- At no point this season have the Kansas City Chiefs looked up at the scoreboard and seen themselves trailing, and head coach Andy Reid admits early successes in each of their three wins starting the season might build some complacency in a defense ranked 29th in the league in scoring and yielding more than 30 points per game.
"Whether it's easing back just a step and then the ball is completed in front of you or you're either late on breaking it up or missing a tackle, that sort of thing," Reid said. "That's human nature, but you have to fight in that sort of situation."
The Chiefs not only have never trailed in a game this season, opponents barely get a chance to share the lead. Reid's offense scored first in each of their first three games, and they've only been tied for 16 minutes, 51 seconds this season.
Reid's team seemingly knows how to start fast. Closing games, however, remains a different matter.
The Chiefs have outscored their opponents 49-6 in the first quarter so far this season. But the defense ranks 27th in the league in second-half scoring, allowing 49 points after halftime through three games. That includes allowing 17 second-half points to San Francisco on Sunday,
"We've got to work both sides of the ball in the third quarter and get that straightened out," Reid said. "A ton of things to work on."
Having a healthy defense would certainly help the Chiefs, and the injury bug bit again Sunday. Linebacker Dee Ford, who shares the team lead with two sacks on the season, left the game with a sore groin. He underwent an MRI Monday to determine the severity. How much, if any, time he misses remains unknown.
If Ford misses action, the Chiefs must lean on second-round draft pick Breeland Speaks and 2016 second-round selection Tanoh Kpassagnon opposite Justin Houston. The Chiefs have worked Speaks and Kpassagnon into the edge-rush rotation starting this season, but Ford and Houston both account for more than 80 percent of the team's snaps, including more than 90 percent against the 49ers.
"We'll see how he does here but I'm glad we've had an opportunity to play those guys and give him a little experience here," Reid said. "They've been rotating in so I'm not as worried as if they had zero experience there."
Safety Eric Berry remains on the sidelines with a sore heel. He hasn't practiced since Aug. 11, and Reid won't know until Thursday whether Berry returns this week.
"I'll probably know a little bit more in the next couple days," Reid said. "It's just status quo right now."
The Chiefs are also slowly working linebacker Reggie Ragland back into the mix. Ragland missed much of training camp with a swollen knee due to an offseason training injury. He saw more playing time against the 49ers, but the Chiefs continue rotating in linebacker Terrance Smith in nickel passing situations.
"Reg, I think the more he plays the better," Reid said. "He is one of those guys that didn't have much time in camp, and he's a big guy that we are asking to do a lot of things with. The more he does it, he just needs to keep playing."
The Chiefs travel to Denver in Week 4 to battle the Broncos on Monday night. The AFC West battle poses the next test for the Chiefs' defense and if they can clean up the second-half mistakes that have turned big leads into closer-than-expected finishes.
"We're a young football team and so you have to learn that," Reid said. "You got to power through that and learn as you go how to finish those type of things."
LB Dee Ford planned to undergo an MRI Monday after exiting with a sore groin in the team's 38-27 win over the San Francisco 49ers.
WR Chris Conley briefly left Sunday's game with a right ankle injury but later returned and caught a 4-yard touchdown pass from Patrick Mahomes. Conley said after the game he expects to be fine for the team's Monday night trip to Denver next week.
S Eric Berry missed his third-straight game and has not practiced since Aug. 11. The team plans to re-evaluate his status when they return to practice on Thursday.
RB Spencer Ware entered Sunday's game as questionable after taking a day off from practice last week to rest his surgically repaired knee. He played 18 snaps against the 49ers as Kareem Hunt's primary backup.
LB Ben Niemann sat out Sunday's game with a hamstring strain, but he could return to action in Week 4 against the Denver Broncos.
WR Marcus Kemp caught the first regular-season pass of his career against the 49ers. Kemp joined the Chiefs last season as an undrafted free agent from Hawaii.
QB Patrick Mahomes set a new NFL mark against the 49ers with his 13th touchdown pass in the first three games of the season. He eclipsed Peyton Manning's mark of 12 touchdown passes during the first three games of the 2013 season. Mahomes needs three touchdown passes this week against Denver to match Manning's record of 16 through the first four games of the season.