[1] As the defending champions, the Steelers opened the season by hosting the NFL Kickoff Game on Thursday, September 10, 2009, which was an overtime victory against the Tennessee Titans.
The team compiled a 6–2 record over the season's first half, but then began a five-game losing streak which included losses to all three division opponents.
[11] In addition, they were forced to address the loss through free agency of two key contributors: starting cornerback Bryant McFadden and number three wide receiver Nate Washington.
[12] The front office and coaching staff also had to focus on uncovering for eventual replacements for some aging cogs: defensive end Aaron Smith[10] and cornerback Deshea Townsend, who were 33 and 34 respectively at the start of the season.
[12] ESPN's Matt Williamson ranked the team's pre-draft needs as (in order), defensive end, offensive tackle, wide receiver and cornerback.
By this measure the Steelers have the fourth easiest schedule in the league – only the Packers, Vikings and Bears opponents have a worse cumulative 2008 winning percentage.
However, in the second quarter, the Bears answered with quarterback Jay Cutler completing a 6-yard touchdown pass to tight end Kellen Davis.
Pittsburgh would strike first in the first quarter with kicker Jeff Reed's 19-yard field goal and quarterback Ben Roethlisberger's 27-yard touchdown pass to running back Willie Parker.
at Heinz Field, Pittsburgh, Pennsylvania Hoping to snap a two-game losing skid, the Steelers went home, donned their throwback uniforms, and prepared for a Week 4 Sunday night duel with the San Diego Chargers.
Pittsburgh would answer the call with kicker Jeff Reed booting a 46-yard field goal, followed by linebacker James Harrison causing a sack and a fumble.
In the second quarter, the Steelers would deliver a big strike with quarterback Ben Roethlisberger completing a 15-yard touchdown pass to tight end Heath Miller.
Detroit tried to rally in the fourth quarter as quarterback Daunte Culpepper found wide receiver Dennis Northcutt on a 25-yard touchdown pass, but Pittsburgh's defense made a crucial stand with three-straight sacks (courtesy of linebacker LaMarr Woodley, cornerback William Gay, and linebacker Lawrence Timmons), followed by cornerback Ike Taylor swatting away the Lions' last hope from a hail-mary pass.
at Heinz Field, Pittsburgh, Pennsylvania Coming off their road win over the Lions, the Steelers went home for a divisional match with the Cleveland Browns.
at Heinz Field, Pittsburgh, Pennsylvania Coming off their divisional win over the Browns, the Steelers stayed at home for a Week 7 interconference duel with the 6–0 Minnesota Vikings.
at Heinz Field, Pittsburgh, Pennsylvania Coming off their impressive Monday night road win over the Broncos, the Steelers went home for a divisional rematch with the Cincinnati Bengals with first place in the division on the line.
Backup Charlie Batch also was hurt in that game, which left 2nd-year QB Dennis Dixon, who previously had one pass in his NFL career, to start.
The Ravens answered on the following drive, with a 52-yard strike from Joe Flacco to Mark Clayton, setting up a 10-yard touchdown pass to Derrick Mason.
In the third quarter, on the Ravens opening possession, Mark Clayton made a 9-yard reception but fumbled the ball and it was recovered by Tyrone Carter.
They also no longer controlled their playoff destiny, needing to win their final three games of the season, and also losses by other AFC teams to have a chance for a wild card.
The Steelers answered with a 34-yard field goal, but would lose the lead for the first time in the game when Ryan Grant rushed for a 24-yard score, putting Green Bay up 28–27.
The Steelers would once again answer with a 43-yard field goal, but Aaron Rodgers would complete a 24-yard TD pass to James Jones and follow it with a successful 2-point conversion attempt.
With just 3 seconds remaining, Ben Roethlisberger would hit Mike Wallace in the left sideline of the endzone (in a TD pass that resembled the Super Bowl-winning catch by Santonio Holmes back in February) and the extra point was good, giving the Steelers a last-second 37–36 win over the Packers.
Jeff Reed booted 26-yard and 39-yard field goals and Billy Cundiff kicked a 27-yarder to give the Steelers a 6–3 lead as they started the second quarter.
But in the final seconds of the first half, Ben Roethlisberger found Santonio Holmes for a 24-yard TD pass, and the Steelers carried a 20–10 lead with them into halftime.
Baltimore had one more chance to score, but rookie defensive end Ziggy Hood recorded his first career sack and then recovered Flacco's fumble on a fourth and 10 play from the Steelers' 39 with 2:27 remaining.
An apparent interception thrown by Roethlisberger was negated by an "illegal block in the back" penalty and the Steelers ran out the clock, securing the win.
Following Reed's 21-yard field goal to start the final quarter, Miami rallied back with the help of fourth-string quarterback Tyler Thigpen.
The Steelers beat four eventual playoff-bound teams: the Green Bay Packers, the Minnesota Vikings, the Baltimore Ravens, and the San Diego Chargers.
However, it was later discovered that Brian Cushing of the Houston Texans, who was named to the AP's second-team at outside linebacker, had tested positive for a banned drug during the season.
The AP chose to re-open balloting and Harrison and Lance Briggs of the Chicago Bears leapfrogged Cushing and made the second-team.