Playing barely 48 hours after a long trip from London at the end of the Premier League season, the two sides nevertheless put on an entertaining show at the cavernous Melbourne Cricket Ground.
Maddison fired Spurs ahead in the 32nd minute before Alexander Isak netted to level the scores on the cusp of half-time.
With mass changes after the interval, neither side could deliver the winner with the game ending 1-1 and going to penalties, which appeared to be a surprise to the players.
Spurs' winger Bryan Gil's opening effort was saved, with Newcastle making no mistakes to win 5-4.
"It was a decent game, the first half was all good and the second half did feel like a friendly," said Tottenham boss Ange Postecoglou. "But I think there was enough there for the punters to get something out of the game."
It was a solid effort on a chilly night given both teams boarded a plane just hours after the season ended on Sunday and effectively lost Monday on the 24-hour journey.
Eddie Howe started eight of the Newcastle team that won against Brentford on Sunday, while Spurs also fielded eight of the side that beat Sheffield United.
They included Newcastle defender Kieran Trippier and Maddison, who came through unscathed in a relief for England manager Gareth Southgate.
Both were included in England's provisional Euro 2024 squad this week, as was Newcastle forward Anthony Gordon, who did not travel to Australia as he recovers from a calf injury.
Spurs enjoyed the bulk of the early possession, but the chances were few and far between with the first serious effort in the 21st minute when Maddison whipped a long-range strike wide.
But Postecoglou's side kept pressing and the opener came after a sloppy clearance by Newcastle keeper Nick Pope landed with Maddison who dribbled past two men and lashed the ball into the top corner.
Pope made amends with a point-blank save minutes later to keep Newcastle alive and they equalised just before the break, with Swedish striker Isak tapping in from close range after Jacob Murphy's low cross.
With a string of changes in the second half, the standard slipped as both sides searched for the winner, with Spurs seeing most of the ball without being able to deliver the killer blow.
While Tottenham's season is now over, Newcastle have another friendly against an A-League All Stars side on Friday, again in Melbourne.
