Another Leesider, Paul Townend, was third on favourite Faugheen, with Melon second.
Samcro edged a titanic tussle with Melon to prevail in a photo-finish at the end of a memorable edition of the Marsh Novices' Chase at Cheltenham.
The pair flashed past the line almost inseparable, but Samcro rallied when he had to and won by barely a whisker - officially a nose - with admirable veteran Faugheen just a length further behind in third, as Irish horses dominated the finish.
It was redemption for Samcro, who lost his form so alarmingly at times following his 2018 Ballymore Novices' Hurdle victory but has now doubled his Festival tally.
After home hope Itchy Feet unseated his rider with a circuit still to run, the Irish contingent took over - and it was Gordon Elliott's Samcro and Russell who proved just the best at 4-1, from Willie Mullins' brave runner-up Melon.
Russell was full of praise for Samcro's winning performance, and admitted he was far from sure they had got the better of Patrick Mullins on Melon - until the photo-finish result was announced.
"It was perfect," he said. "He missed the second last, winged the last and went ahead to win.
"Patrick's horse battled very gamely - I thought he'd just chinned me.
"He actually headed me - but to be fair to my horse, he was so game. He's as brave as a lion, and he got back up in the last stride."
Elliott added: "He's the forgotten horse, but he's one of the favourites in the yard. We love him, he's brilliant."