Let's make one thing clear at the outset: NFL Xtreme is no NFL Blitz. Despite appearances to the contrary, it doesn't look, sound, or play even remotely like the original (and still the best) arcade-style football game. This isn't really surprising - an NFL Blitz machine utilizes state-of-the-art hardware and costs thousands of dollars, while the PlayStation is some three years old and lists for around a hundred bucks. Even so, there has been a handful of arcade-quality games released on the PlayStation (Tekken 3 and Rage Racer, to name two) - we just want to make it clear that NFL Xtreme isn't among them.
So, if NFL Xtreme isn't a legitimate NFL Blitz competitor, what exactly is it? As far as we can tell, NFL Extreme appears to be a five-on-five version of Sony's excellent but now aging GameDay '98. (For its part, Sony maintains that NFL Xtreme does not use the GameDay engine, but whether it does or doesn't is beside the point, because the differences between the "two" engines, if indeed there are two, are very few and very far between.)
Because of its close similarity to GameDay, which was designed for standard play, NFL Xtreme largely fails to take advantage of the unique gameplay opportunities presented by a five-on-five football format. The best example of this is in the playbook, the core of any football sim. The idea of a five-on-five game is that the field is wide open, and as a result, the gameplay should be free-flowing and creative. But in NFL Xtreme, it simply isn't. You're straightjacketed into run-of-the-mill plays - sweeps, outs, posts, etc. - that we've all seen, run, and defended against many times before. Furthermore, you have absolutely no latitude to customize the plays or to make them more interesting while running them. With one exception (the halfback pass), multi-pass plays are not possible. Downfield laterals are a no-no. And you can't send your men into motion.
Another major issue is the control, which is sluggish and generally "off" just enough to become a major impediment to enjoying the game. Catching a pass is an adventure each and every time - you can hit the same player in the same spot two plays in a row and get completely different results. Dropped passes, players inexplicably pulling up during their route, passes bouncing off the receiver's helmet - if you want ways to go crazy playing offense, this game has got 'em in spades. And success on defense seems even more random than on offense - it's basically pick a play and hope for the best.
So, we've established that the playbook is lame and the control is suspect. What about NFL Xtreme's highly touted graphics engine? Well, it does have its moments - there are some absolutely vicious hits, the players are highly detailed, and the frame rate is impressive (at times). But overall, as with the control, something isn't quite right. The collision detection is less than perfect, so players routinely run right through each other, destroying any sense of realism. And the graphics are often extremely murky in the middle of the screen, especially during running plays (which, incidentally, must almost exclusively be run to the outside in order to gain positive yardage, a trademark of second-tier football games).