Brandon Lloyd dives headfirst for a Tom Brady spiral sizzling across the middle of the field. But just as he reaches out and gets his fingertips on the ball, Troy Polamalu’s vicious shoulder arrives, and as the two players collide, B-Lloyd is sent twirling like a helicopter as the rock flies out of his hands and is picked off by a nearby Steeler.

Welcome to the new Infinity Engine in "Madden NFL 13," a game-changing physics system that incorporates a player’s weight, center of mass, body type and height into every action, making each movement on the field more dynamic as ball carriers struggle and fight for yards.

This is the biggest change to the “Madden” franchise this generation, and the biggest upgrade, maybe ever. The predetermined outcomes of past football games are history. Collisions look and feel more authentic, and with every tackle based on pure physics, you won’t keep seeing the same tired animations play out over and over again like past iterations. You’ll see a running back like Chris Johnson, who might stumble as a defender reaches out and grabs his foot, but now has the ability to recover and burst downfield, hurdling over the last diving defender in his way. Blocking is now more organic, as the new physics engine eliminates the frustrating old days of polygonal body parts passing through each other, so now, when a guard pulls, he’s not morphing to a spot or sticking his arm through the defender in order to pancake the linebacker. In “Madden 13,” the players are scratching and clawing for position, making every movement count as they throw around that weight and momentum to some mind-blowing consequences.

This is a physics-driven animation engine that layers on top of “Madden’s” older animations and augments every outcome you’ll see in the game. Every scenario will now see players' muscles tuned to an appropriate strength, so if your quarterback is hit from the blind side you’ll see him wobble in an appropriate manner, or if you’re a receiver jumping into the air for a pass, his muscles will be more tense when running but loose when he leaps into the air, since he doesn’t have anything to lean on. So if a receiver is smashed by a defender while reaching for the ball, the violent reaction will be unleashed.

In addition, now as you crash through the line with the ball, you have to be careful not to run full speed into your own lineman, forcing you to actually follow your blockers, not run right through them (or pay the consequences with lost yardage). You also need to watch out for that tackler who whiffed on his dive but is still in front of you on the ground. If you don’t hurdle or sidestep, now you'll trip over him on the turf. And if your running back falls down on another player, but his knees don’t touch the ground, you can actually roll off the tackler, get up and keep running. In “Madden 13,” the interactions don’t end until the whistle blows.

Playing the game as the 49ers, Frank Gore was running the ball when Roman Harper ran up to make the tackle. Gore attempted to stiff-arm the Saints safety, but Harper had a good grip on Gore until out of nowhere, Vernon Davis ran up and de-cleated Harper, enabling Gore to gallop into the end zone for the score. In “Madden 12,” once the defender started to wrap you up, the tackle was already predetermined, and it didn’t matter what the offense was going to do, Gore was going down. This year, like I said, it’s about fighting for every yard because you just don’t know what’s going to happen next.

But the Infinity Engine isn’t the only huge feature being added to “Madden 13,” as the game’s designers are completely changing everything you know about Franchise mode with an innovative new take entitled Connected Careers.

EA Sports refers to Connected Careers as the “first true sports RPG,” and the mode enables you to play as a coach and control your entire team, or as any skill player in the NFL and take over their career (sorry, no punters allowed). If you want to play as the 49ers' third-string quarterback, the choice is yours. Want to coach the Patriots? Time to take control and see whether you can out-hoodie the master. Or maybe you want to start out as a rookie legend like Joe Montana or even coach John Madden himself (30 legendary players and coaches have been signed to appear) and see if you can put up the same numbers and win the amount of awards and championships that these legends did in real life. You can even fully customize your own fictional player or coach, and you’ll be given a backstory of the high draft pick looking to fulfill expectations or the undrafted rookie looking to prove himself on the field, with your backstory determining your starting ratings and abilities.

You can then create or join an online public or private league and compete against friends or strangers in anything from a player-only league to a quarterbacks-only league to a combination of coaches and players all competing at the same time.

Throughout your career, every player and coach will be given a checklist of weekly, seasonal and milestone goals (over 900 in the game). By achieving these goals through both games and practice scenarios, you’ll earn experience points (XP) you can then spend to improve your character, turning him into the power runner or sticky-handed cornerback you envisioned.

The best part is, anytime you get sick of your current player or coach, or if you just want to try out a new position, you can simply retire and start over in the same league as any other player or coach who hasn’t already been selected. This means you can play ten years as a wide receiver, retire, then decide to coach the Browns without having to start a new league.

But that’s not all, as there will be a series of dynamic events that will take place throughout your career that will continue to flip the storylines in fresh, and sometimes unbelievable, directions.

Say you’re a coach looking for the next great receiver. You might have your eye on somebody in particular and scout him hard, but at the combine the player tears his ACL or the night before the draft a player chooses to play in the NBA. You might even see certain coaches from the past come out of retirement to take control of one of your rivals, or a quarterback whom you thought was retired might just sign with a team that is seemingly one player away from the Super Bowl.

To add to the storylines, Connected Careers will add constant virtual Twitter feeds of 13 sports journalists, meaning you’ll read the thoughts of Skip Bayless as he rants and raves about how this “Joe Montana kid will never make it as a big-time NFL quarterback” before the draft. The journalists will even break stories based on what you’re doing in your career. So if you’re the coach of the Raiders and you start scouting quarterbacks, Adam Schefter will tweet that “Oakland is leaning toward taking a quarterback in this year’s draft,” alerting everyone in your league to your plans. This makes scouting and the draft process a lot more exciting.

In terms of free agency, the new system is set up more like recruiting from EA’s “NCAA Football” series, where you’ll be fighting with the other coach-led teams to convince a player to sign with your squad. And based on each team’s system, you’ll actually see players have different player ratings (Dynamic Team Ratings) based on how each coach evaluates how certain characters will fit with their teams.

And for the first time in “Madden” franchise history, computer-controlled teams will make trades with each other and offer deals to human-controlled teams. All-new trade logic has been entered into the game, with teams evaluating and valuing players based on how they see each player fitting into their lineup. Adding to the trade logic is a brand-new sim engine that actually has teams planning for both the present and the future. In past games, if a team needed a quarterback, it would just take the highest-rated player on the board in free agency, not even looking at the draft. Now teams who need a quarterback will also look forward to the draft to see whether a player like Andrew Luck is available before simply signing an older player to a lucrative contract.

In checking out the mode for myself, Connected Careers really does seem like the perfect blend of Franchise, Online Franchise and Superstar mode, as you can now play the game however you want to play. Whether you want to control your entire team, your roster and playbook, or if you simply want to take over the likes of Tim Tebow and see whether you can snatch the starting quarterback job away from Mark Sanchez and lead the Jets to the Super Bowl, it’s entirely up to you, with the payoff finally coming when your player makes the Hall of Fame.

This is a new vision for career mode, and since this isn't just an isolated console experience, but truly connected play in which you can share stats, stories, and smack talk with other “Madden” gamers -- even comparing your overall legacy score the game gives you based on your accomplishments -- it’s really pushing the genre forward. This adds a new way to compete in “Madden” as you can compare your legacy score to not only other gamers from around the world, but to current players in the NFL or even an NFL legend like Jerry Rice. You’ll also be able to join league Twitter accounts in order to get updates throughout the day, even when you’re not on your console.

Forget the days of saying the new “Madden” is just another roster update. “Madden 13” looks to completely change the game (and it’s about time!).