KANSAS CITY, Mo. -- The Kansas City Chiefs were quick to point out after Sunday's 30-24 loss to the Los Angeles Chargers that it's almost impossible to win an NFL game when turning the ball over four times, as the Chiefs did.

That's true, but since Patrick Mahomes took over at quarterback Kansas City generally hasn't been consistently sloppy with the ball. Sunday's turnover problems are a seemingly easy fix.

Repairing the bigger issue, a leaky defense, will be more problematic. The Chiefs, after a strong start on Sunday, allowed the Chargers to score on five of their final seven possessions, including all three in the fourth quarter. The Chargers were 4 of 5 scoring touchdowns in the red zone, making Chiefs opponents 12 of 13 in that category this season.

The faulty defense, which also wasted an 11-point fourth quarter lead during last week's loss to the Baltimore Ravens, is the biggest reason the Chiefs are 1-2 and in last place in the AFC West for the first time since 2015.

The Chiefs are allowing almost 32 points per game. They entered Sunday's game last in the league in total defense and rushing defense and it took them some time to get into this state defensively. It may take some time for them to get out of it as well.

Here are some factors playing into why the Chiefs have struggled on defense:

They've opted to put a lot of their resources the past couple of years into their offense. Since rebuilding their defense following the 2018 season, the Chiefs have invested mainly in offensive players. Their first-round draft pick last year was a running back, Clyde Edwards-Helaire. They traded their first-round pick this year for an offensive tackle, Orlando Brown. Their big-money free agent signing this year was a guard, Joe Thuney. In all, the Chiefs between the draft, a trade and free agency acquired six new offensive linemen and left the defense mostly intact.

The result is a unit that has just two former first-round draft picks. Cornerbacks Mike Hughes and DeAndre Baker were once low first-round picks by other teams and discarded by those clubs for little or no return.

The trade for and big contract given to defensive end Frank Clark doesn't look as good as it once did. Clark helped the Chiefs win Super Bowl LIV two years ago and helped them get back to the Super Bowl last year, but they've received little from him this year. Clark missed much of training camp and all of the preseason with hamstring injuries. He hasn't played in two of this year's three games, including on Sunday against the Chargers.

The Chiefs pass rush has struggled, even when he's been in the lineup. They entered Sunday's game last in the league in pass rush win rate at 26.2%. The Chiefs acquired Clark to pair with Chris Jones in the pass rush but Jones hasn't been effective the past two weeks, though he did have two sacks in the season-opening win over the Cleveland Browns.

Recent high draft picks the Chiefs have used on defensive players have yielded little help. In 2018, the Chiefs traded up to make defensive end Breeland Speaks their top draft pick in the second round. He lasted two unproductive seasons before being released. They drafted a linebacker, Dorian O'Daniel, in the third round the same season and while he's still with the Chiefs, he's almost exclusively a special teams player.

The Chiefs in 2019 drafted a safety, Juan Thornhill, in the second round and a defensive lineman, Khalen Saunders, in the third. Both players are backups. They drafted linebacker Willie Gay in the second round last year but he was mainly a backup as a rookie and hasn't played this year because of injury.

And as far as the offense goes: All of this has put a lot of pressure on the offense, which was good enough to score 33 points and win the opener against the Browns and score 35 last week against the Ravens. The Chiefs, despite the four turnovers, scored 24 points against the Chargers.

But it might continue to be difficult for the Chiefs to score enough to overcome their defense. Opponents are working to limit the Chiefs' big plays. They faced two high safeties in their first two games on 82% of their plays, far higher than the league average of 64%.

The Chiefs had trouble navigating that in the second half against the Ravens with two turnovers and against the Chargers with four.