On a sodden Headingley pitch neither side produced much in the way of flowing rugby, with Leeds enjoying the better of the opening exchanges despite fullback Steve Jones countering well for the Falcons as he jinked his way through the defensive line on more than one occasion.
England Under-18s fly half Rory Clegg played the full 80 minutes on his first team debut, steadying the nerves with a bone-crunching ball-and-all tackle early on before probing the corners with a string of grubber kicks.
Lock Geoff Parling produced a fine line out steal just five metres from his own corner to thwart Leeds, in a half bereft of creativity from either team.
With the Falcons turning down kickable penalties to opt for the try line, the closest the visitors came to scoring in the first half was a blindside attack down the right as Tom Dillon's neat inside pass narrowly failed to find support runner Tom May, as Newcastle trailed by six at the break.
A more lively second half saw six tries in all, three apiece, with Leeds striking first as American prop Mike McDonald barelled over down the right hand side.
Newcastle hit back as replacement wing John Rudd burst through two tacklers and sped to the try line from 20 metres out, Jones adding the extras with a marvellous touchline conversion from out wide on the right.
With the Falcons now in the ascendancy their second try was not long in coming, flanker Tim Swinson being the man to pounce with a powerful pick-and-go as he supported breaks from James Grindal and replacement flanker Brent Wilson, who added energy aplenty throughout the half.
Newcastle looked to have clinched the victory when a jinking run from Jones saw the Scotland 'A' man claim a deserved try, with former Leeds Rhino Danny Williams playing a key role in the build-up as the rugby league man made a surging diagonal run.
Jones again converted for a 21-11 lead, but with Newcastle piling on the replacements for the last ten minutes the balance shifted onc more as Leeds flanker Calum Clark crossed the try line from short range on an inside angle.
Alberto Di Bernardo's converson clawed te hosts back to within three points, before a last-minute score from Tongan internationa hooker Viliame Ma'asi clinched the result for the Yorkshiremen.
Speaking after the game, Falcons director of rugby, Steve Bates, said: “We're obviously disappointed to have lost it at the end, but the boys had a good 80-minute work-out today, which was the main goal.
“We made a lot of changes for today to look at some different combinatons, and while there are some positives to take from it, there is also plenty of room for improvement.
“We now head to France for a week's training camp which gives us some quality time as a group to work on what needs to be done, and next Sunday's game against Racing-Metro will see us field something close to what our starting line-up will be for the Sale Sharks game on September 7, with a match-day 22 rather than the raft of replacements we have used for the two previous friendlies.
“We will look to involve Jamie Noon in some form for that game after his rest period, and while Jonny Wilkinson will most likely not be involved in Lille, we are hopeful he will be ready for September 7.”
Leeds Carnegie:
Tries: McDonald, Clark, Ma'asi
Cons: Di Bernardo 2
Pens: Strange 2
Newcastle Falcons:
Tries: Rudd, Swinson, Jones
Cons: Jones 3
Newcastle Falcons:
15 Steve Jones
14 Tom May
13 Tom Dillon
12 Spencer Davey
11 Tim Visser
10 Rory Clegg
9 Hall Charlton
1 Jon Golding
2 Matt Thompson
3 Carl Hayman
4 Andy Perry
5 Geoff Parling
6 Adam Balding
7 Ed Williamson
8 Russell Winter (captain)
Replacements:
Johnny Williams, Micky Ward, Rob Vickers, Andy Buist, Mark Sorenson, Brent Wilson, Tim Swonson, James Grindal, John Rudd, Danny Williams, Andrew Fenby.
