CHARLOTTE, N.C. — During the first quarter of the season, Carolina Panthers coach Ron Rivera dealt with: a mobile quarterback who is not currently mobile, injuries to his top four other ball carriers, a Pro Bowl defensive end on the NFL’s exempt list and a suddenly leaky defense.

Despite all that went wrong, including consecutive losses by a combined 46 points, the Panthers are somehow tied for the division lead.

At 2-2, Carolina and the Atlanta Falcons are one game ahead of the New Orleans Saints and the Tampa Bay Buccaneers in the disappointing NFC South.

“There’s a lot of negatives and a lot of things to beat ourselves up over, but there’s no time to panic,” Rivera said Monday. “There’s still a lot of hope now. I just hope we understand that.”

While the Panthers are technically in first place heading into Week 5, there are plenty of reasons for legitimate concern.

Quarterback Cam Newton has just eight carries on the season, and the running back situation remains a mess. Starting running back DeAngelo Williams, who returned after missing two games because of a hamstring injury, tweaked his ankle in the first half of Sunday’s loss to the Baltimore Ravens.

Rivera said Williams is doubtful for this week’s game against the Chicago Bears.

Backup running back Jonathan Stewart is still hampered by a knee sprain, and fullback Mike Tolbert will not return from a hairline fracture in his leg until after Thanksgiving, at the earliest.

No. 4 back Fozzy Whittaker is expected back this week, but he is dealing with a sore quad that forced him to sit out the last two games, so, the Panthers signed running back Chris Ogbonnaya on Monday and waived running back Tauren Poole.

Ogbonnaya, 6 feet and 225 pounds, spent most of the past three seasons with the Cleveland Browns. In 2013, he played in 16 games and made seven starts for the Browns, totaling 240 yards on 49 carries and 343 yards and two touchdowns on 48 receptions.

In his career, Ogbonnaya has played in 46 games with 12 starts, rushing 144 times for 660 yards and one touchdown. He also has 96 receptions for 714 yards and two touchdowns.

Before the signing, the Panthers were down to using undrafted free agent Darrin Reaves, who had 12 carries for 26 yards against the Ravens.

“I feel blessed to be in the position that I’m at,” said Reaves, a UAB product. “A lot of guys come out of free agency, coming from the school I came from, they don’t make it.”

The Panthers have issues to address on defense, too.

After giving up 37 points to the Steelers, they allowed the Ravens to score 38. The only other time the Panthers surrendered 35 points or more in back-to-back games was in 1998.

Over the past two weeks, Carolina fell from second to 17th in points allowed per game, from fifth to 23rd in total yards allowed, and from sixth to 27th in rushing yards allowed.

The Panthers have only one sack since defensive end Greg Hardy went on the league’s exempt list in Week 3, and since his legal situation remains unclear, the team is unlikely to get the Pro Bowler back anytime soon.

As bleak as things appear at the moment, the fact remains: The Panthers lead the division. For now.

“We’re right in the thick of things,” Rivera said. “We are above water right now, but if we’re not careful, we can go under water.”