England ran out 1-0 winners at Deepdale in their final warm up game ahead of their qualifying campaign.
But it was at the other end of the pitch that provided all of the action, with England creating a number of chances, before finally making them count through James Wilson on 72 minutes.
Sunderland man Duncan Watmore squared the ball back towards Wilson from the by-line and the Manchester United striker slotted it past Cropper.
Wilson almost doubled England's lead just moments after his goal, but his wonderful dipping shot from distance came off the post afer beating Cropper in the USA goal.
England had dominated for the majority of the game, and certainly had the better of the chances in the first half.
Inside ten minutes, England almost took the lead through Calum Chambers, but his looping header dipped just over the bar and on to the roof of the net.
Liverpool man Jordan Ibe was on form early on, and his superb ball in to the box was met by some great control from Dele Alli, who chested it down and fired at goal but it was well per the bar.
On the twenty minute mark, PNE's on loan 'keeper Pickford was called into action for his first real save of the game, it was a powerful effort from Rodriguez but the PNE 'keeper, at full stretch, tipped it around the post.
It was all England in the first 45 minutes and it was Cauley Woodrow who provided one of the best chances of the first half, he was one-on-one with Cropper but fired straight at the USA 'keeper.
It was Woodrow again causing problems for the visitors five minutes later with a chance on the half hour mark, but he forces a great save from Cropper from six yards out.
It was a let off for England, with five minutes of the first-half remaining, after a defensive mix up, Hernandez picks up the loose ball and has a shot from the by-line but hits the side netting.
On the stroke of half-time, Ibe broke through the USA defence and fired at goal from inside the box but his effort was well over the bar.
It was followed by a free-kick for England as Ibe was brought down just outside the box. Ward-Prowse fired towards goal but Cropper saved it down low and that was to be the last of the first half action as the referee blew for half-time.
There was little in the way of chances early on in the second period, with USA coming out the stronger side in the early stages after the break.
Ward-Prowse with the first real effort for England in the second half ten minutes in, with a powerful shot from distance that forces a strong save from Steffen.
Brilliant from Ibe who bursts into the USA box after a driving run, but he takes too long to decide between a cross or a shot and the ball was won by the USA defence.
England started to pile the pressure back on the visitors creating plenty of chances, but the organised USA side stood strong.
On the hour mark there was an plethora of changes, as Gareth Southate made nine changes, including PNE 'keeper Pickford, who was replaced by Angus Gunn.
The North End 'keeper making a solid start to his England U21 career with a clean sheet, and will be hoping to make the starting Xl for Monday's European Championship qualifier.
It wasn't until the 72nd minute that England found their breakthrough, and it came through James Wilson, who had an easy finish after he was set up perfectly by Watmore.
England almost doubled their lead just moments later through Wilson again. It was a beautiful dipping effort from the Manchester United striker, he had the 'keeper beaten but it bounced off the post and out.
Lovely ball from Wilson who tried to repay the earlier assist by setting up Watmore. The Sunderland striker was one-on-one with Steffen in the USA goal but fired well over the bar from inside the box.
There was little in the way of chances in the remainder of the game, but England U21 boss Southgate, who was celebrating his 45th birthday on the night, will be satisfied with the victory ahead of Monday's qualifier.
England line-up: Pickford (Gunn, 60), Gomez (Iorfa, 60), Targett (Stephens, 60), Loftus-Cheek, Chambers, Dier (Hause, 60), Ibe (March, 60), Ward-Prowse (Chalobah, 60), Woodrow (Watmore 60), Alli (Forster-Caskey, 60), Redmond (Wilson, 60).
USA line-up: Cropper, Okwuonu, O'Neill, Trapp, Hyndman, Hernandez, Pelosi, Miller, Kiesewetter, Rodriguez, Miazga.
USA subs: Steffen, Carter-Vickers, Packwood, Serna, Ariyibi, Gil, Joya, Horvath, Sorto, Polster, Rubin, Tall.
Referee: Mr A Mario
Post-match reaction from Jordan Pickford can be found on PNE Player HD now by clicking here.