PITTSBURGH -- First Le'Veon Bell, now this.

The Steelers' already fragile season twists in the wind as Ben Roethlisberger left the field in a cart midway through the fourth quarter after hurting his left foot on an Aldon Smith sack. Roethlisberger appeared to get his foot caught underneath Smith, who dragged Roethlisberger down from behind.

The Steelers have survived injuries all year and have kept things together with a 5-4 mark, beating Oakland 38-35 thanks to the wizardry that is Antonio Brown. If Roethlisberger is out for an extended period, it's hard to think they'll survive this and make the playoffs.

There’s only so much a team can take. While Roethlisberger missed four weeks with a sprained MCL, the offense never scored more than 24 points in those four games.

And to think the Steelers were recording their most explosive performance since Week 2, with Roethlisberger and Brown connecting for 180 yards in the first half. Roethlisberger finished with 334 yards, two touchdowns and an interception. Brown finished with a colossal 284 yards on 17 catches.

In a span of 41 seconds early in the fourth quarter, Martavis Bryant shook four defenders on his way to the end zone, Roosevelt Nix cued a collective “oooooh” inside Heinz Field with a special-teams strip-fumble and seldom-used rookie Jesse James caught his first touchdown pass in the back of the end zone.

This, Pittsburgh fans, was the explosive performance you expected when the season started. This is a team, at its core, that can reach for the driver and go 350, all fairway.

But they need to be healthy. Roethlisberger's injury changes all that.

The immediate goal: Get to 6-4 at the bye and get equipped for a playoff run, which isn’t a guarantee even with Roethlisberger, and an especially arduous task without him.

What it means: There’s a lot to like about this performance. Several offensive playmakers went off, and the defense created multiple turnovers once again. The Steelers sensed the urgency of this game and made plays. The defense over-blitzed late in the game, leaving Michael Crabtree one-on-one with linebacker Lawrence Timmons for a score. But if the Steelers have any hopes to survive these injuries, the defense must continue to create turnovers.

What were they thinking? The Steelers’ pass coverage had multiple breakdowns in communication, resulting in a wide-open Amari Cooper touchdown in the back of the end zone and Seth Roberts' too-easy catch for 36 yards to set up a touchdown. The Steelers dropped back into zone coverage and didn’t always account for every receiver. That’s a bad look in Week 9.

One reason to get excited: Safety Mike Mitchell might be overzealous on his post-hit celebrations, even after player injuries, but the dude’s playing well. He has created a turnover in three of the past four games, including a strip-fumble of Raiders running back Latavius Murray.

One reason for concern: After an electric start to the season, Bryant has been off his game the past two weeks. He dropped two passes Sunday. Roethlisberger threw him a beautiful pass down the sideline and Bryant bobbled the catch. He did have a shifty 14-yard touchdown catch off a screen pass, but otherwise, he was quiet.

Fantasy watch: DeAngelo Williams solidified himself as a top-10 fantasy back with a complete performance Sunday, recording more than 170 total yards rushing and receiving along with two rushing touchdowns and a two-point conversion reception. Play him as an RB1 or RB2. He looks explosive in live action and will get enough touches in this offense.

Ouch: Roethlisberger left the stadium for further evaluation on his left foot. Wide receiver Darrius Heyward-Bey briefly left the game with a shoulder injury that was not considered serious. Otherwise, the Steelers left the game in relatively good health.