Down 27-3 at halftime, the Browns used a high-tempo offense to score 24 straight points and tie the game early in the fourth quarter. The Steelers, though, went on a game-winning drive at the end of the fourth, punctuated by Shaun Suisham's field goal as time expired to give Pittsburgh a 30-27 win.
“I told the team afterwards this is a pass-fail league,” Pettine said after the game. “We failed. I’m proud of the effort in the second half but it’s a valuable lesson to learn. You’re behind 24 points at halftime. I don’t know what the percentages are of coming back and winning. I guarantee it’s probably right around one.
"There are no moral victories in this league, but I was proud of the resolve and the character that showed up.”
Browns quarterback Brian Hoyer went 15-for-20 for 173 yards and one touchdown in the second half in leading the comeback.
The loss to the Steelers was Cleveland's 10th-straight season-opening loss, and the Browns haven't won at Heinz Field since 2003.
Cleveland hosts the New Orleans Saints in Week 2 this Sunday.
WEEK 1 PHOTOS FROM AROUND THE NFL
Week 1 of the 2014 NFL Season
While returning a punt against Cleveland, Antonio Brown tried to hurdle Spencer Lanning and ended up drawing an unnecessary roughness penalty when his foot hit the punter in the face.
With eight seconds left in the first half against Cincinnati, Joe Flacco and the Ravens lined up at the 15-yard line for a shot at the end zone. But Flacco instead ran toward the sideline, failed to get out of bounds, and tripped as he attempted this pass. The clock expired.
Wide receiver A.J. Green of the Bengals keeps his eye on the ball, before scoring a touchdown on this play.
Ryan Allen of the New England Patriots has his first-quarter punt blocked by Chris McCain of the Miami Dolphins.
Tony Romo of the Dallas Cowboys found himself on the ground a bunch in a loss to the San Francisco 49ers.
Vernon Davis pulls in one of his two touchdown receptions against Dallas
Antoine Bethea breaks up a pass intended for Jason Witten.
The view before kickoff between the Dallas Cowboys and San Francisco 49ers in Arlington.
Robert McClain of the Atlanta Falcons intercepts a touchdown pass intended for Brandin Cooks of the New Orleans Saints.
Julio Jones of the Falcons loses control of the ball before he can cross the goal line.
Marques Colston lost this fumble in overtime, leading to a game-winning scoring drive by the Falcons.
Fred Jackson dives for the endzone against the Bears but came up short.
Matt Forte had 17 carries for 82 yards in Chicago's overtime loss to Buffalo.
Alshon Jeffery didn't score against the Bills but did pull in five passes for 71 yards.
Brandon Marshall hangs on to an 11-yard pass from Jay Cutler for a third-quarter touchdown.
Jay Cutler threw for 349 yards and two touchdowns but was also intercepted twice in an overtime loss to Buffalo.
Dan Carpenter kicked three field goals in Buffalo's upset win at Chicago, including a game-winning 27-yarder in overtime.
Chicago Bears pregame
The Bears take the field for their season opener.
Brandon Marshall questions an incomplete pass call at the end of the third quarter. The call was challenged and overturned for a complete pass.
New York Jets pregame
A tribute to the late Joan Rivers is seen on the video board at MetLife Stadium during the third quarter of a game between the New York Jets and the Oakland Raiders.
A 71-yard touchdown run by Chris Ivory provided the deciding points for the Jets in their victory over visiting Oakland.
Nick Folk of the New York Jets kicks a field goal against the Oakland Raiders.
Rod Streater gave the Raiders a brief 7-3 lead with this 12-yard score on a pass from rookie Derek Carr.
Derek Carr completed 20 of 32 passes for 151 yards and two touchdowns in a losing effort against the Jets.
In his first game as a Raider, James Jones made three grabs for 36 yards and scored once.
Robert Griffin III
Washington Redskins quarterback Robert Griffin III is sacked by Houston Texans linebacker Brooks Reed (58) and linebacker Mike Mohamed .
Andrew Luck managed to get this ball across the goal line for a touchdown before he went out of bounds.
Wide receiver Hakeem Nicks of the Indianapolis Colts leaps over and is tackled by strong safety T.J. Ward of the Denver Broncos.
Montee Ball accentuates his scoring run with a dive into the endzone.
Jared Cook of the St. Louis Rams makes a catch against Robert Blanton of the Minnesota Vikings. The Vikings beat the Rams 34-6.
Travis Kelce of the Kansas City Chiefs reaches out for the ball in the endzone as Blidi Wreh-Wilson of the Tennessee Titans defends during the second half.
Tight end Tyler Eifert of the Cincinnati Bengals suffered an elbow injury early in the game against Baltimore and didn't return to the game.
Team officials tend to Tyler Eifert.
Derrick Johnson of the Kansas City Chiefs reacts as he is taken off the field during the first half of the game against the Tennessee Titans. He injured his Achilles and could be out for the remainder of the season.
Ron Parker of the Kansas City Chiefs breaks up a pass intended for Justin Hunter of the Tennessee Titans.
Linval Joseph of the Minnesota Vikings celebrates after sacking Austin Davis of the St. Louis Rams.
Ben Roethlisberger looks to pass downfield in front of Buster Skrine of the Cleveland Browns.
Alan Ball of the Jacksonville Jaguars intercepts a pass in the end zone intended for Brent Celek.
Rob Gronkowski celebrates his second-quarter touchdown as teammate Danny Amendola looks on.
Josh McCown is hit by defensive end Charles Johnson of the Carolina Panthers. McCown threw an interception on the play.
Jordy Nelson stepped out of bounds before he could score on this play. He led Green Bay with nine receptions and 83 yards.
New York Jets pregame
The scene at MetLife Stadium.
- Ben Estes