Steelers QB Ben Roethlisberger accepts congratulations from Giants counterpart Eli Manning after Pittsburgh's 24-20 come-from-behind win Sunday. (US Presswire)

This was the most important, the most signature Steelers regular-season victory scored by a Mike Tomlin team against somebody not named the Baltimore Ravens. Pittsburgh on Sunday registered a 24-20, come-from-behind triumph over the Super Bowl champion, something that the Steelers hadn’t done in their previous four attempts and six of their prior nine meetings with a defending champ.

The Steelers (5-3) fairly dominated the Giants (6-3) at their own game, too: Rushed all over them,  converted a fourth quarter comeback by outscoring New York 14-0, and played some vital defense – this after blowing fourth-quarter leads earlier on the road against the lowly likes of Oakland and Tennessee.

Funny, but these Steelers have done enough to lead the NFC East, going 3-0 thus far against the Giants, Washington and Philadelphia. Their 2-3 AFC record, however, makes the next five weeks all the more critical to their playoff hopes: Kansas City next Monday, Baltimore twice in three weeks and Cleveland plus San Diego to follow. 

Offense: A

Ben Roethlisberger went 7 for 8 on third down. ... Isaac Redman, at one point with a banged-up backup the only warm body behind him, rushed for a career-high 147 yards. ... The offensive line not only opened rushing lanes but protected Roethlisberger, especially in the key fourth quarter. Each offensive phase scored highly even if this were an Advanced Placement class. And offensive coordinator Todd Haley deserves extra credit, too: he had the right balance and the right touch (fullback Will Johnson, backup tight end David Paulson, keeping in Heath Miller to help rookie Mike Adams pass block). They scored touchdowns and they ate up considerable clock – it’s the kind of offense that could carry the Steelers far. By the way, Jonathan Dwyer and Redman have combined for four 100-yard games in the Steelers’ past nine games; Rashard Mendenhall, who has as many 100-yarders in his past 29 games, may have to share the ball more often once he comes back (six games missed). Previous game’s grade: B

Defense: A+

The Steelers allowed Eli Manning and the defending Super Bowl champion offense just 182 yards total. It held Manning to 1-for-6 for just one yard on third down, with a sack, a fumble and nary a third-down conversion via the pass. There was no fourth-quarter comeback for Manning, who mostly watched as Roethlisberger directed two final-stanza touchdown drives for his career 30th fourth-quarter comeback win. Three Pittsburgh defensive penalties for 88 yards greatly enhanced New York’s scoring chances, and at one point in the first half the Giants had more yards in Pittsburgh defensive penalties than they gained on their own via offense. And a couple of those calls still had Mike Tomlin grumbling deep into Sunday night – "suspect" was one word he invoked. Cornerback Keenan Lewis has emerged as a solid quarterback, cornerback Ike Taylor garnered just his third interception in 35 games, and outside linebacker LaMarr Woodley applied some pressure from the edge. Previous game’s grade: B-

Special teams: A

Chris Rainey probably had to get oxygen: He ripped off long return after long return without a single flag – a season first. In fact, this rookie averaged a whopping 34 yards per kickoff return, and his last one was smothered officially after 3 yards. The Steelers compiled three returns of 50 or more yards, two on Rainey kickoffs and another on an Emmanuel Sanders punt return -- after Rainey left the game with a rib injury. (He told reporters he expects to play next Monday against Kansas City). Still, the special-teams play that fans long will remember: the abysmal over-the-back pitch to kicker Shaun Suisham, whose early sprint tipped off the Giants’ defense and got snowed under well short of a first down. Previous game’s grade: C

Coaching: B+

Dick LeBeau’s gameplan kept Manning and the Giants off-kilter. Haley’s offensive attack, as aforementioned, vexed a decent Giants defense. Tomlin had the Steelers ready despite an emotional New York and a day-of-game travel schedule for the Steelers. The lone blemish, the one facet that kept the coaches from getting a gold-star A, was the decision to go for a fake field-goal pitch to kicker Shaun Suisham in chip-shot range, when he could’ve kicked the game into a tie. It was a move for a home-field team, not a roader. But the Steelers overcame, mostly due to suffocating defense and confounding offense. Previous game’s grade: B

Follow Steelers reporter Chuck Finder on Twitter @CBSSteelers and @cfinder.