In a disappointing game, Berwick allowed two important points to slip away - but neither team played anywhere near their true form.
After a first half in which Berwick dominated possession but failed to cash in on several chances, danger man Kevin Haynes powered in a Daniel Swanson cross to put Rangers ahead.
They looked comfortable until man-of-the-match Mark Cowan committed his one serious error. He lost the ball; Steve McManus took it to the by-line and laid on a pass for Gary Middleton to aim home.
With their confidence boosted, Montrose took control and Hugh Davidson had two great shots saved by Gary O'Connor.
In the last eight minutes there were two controversial incidents. First Haynes appeared to head cleanly past Sandy Wood, but it was disallowed.
Almost immediately Barry Donnachie was given a straight red card. His foul hardly deserved punishment, let alone a sending off.
With a man advantage Berwick swept forward. New signing Sean Paliczka went past four opponents before finishing neatly, and with the last attack of the game Haynes was inches wide with a great effort.