Dion Charles’ 21st Wanderers’ goal of the season kept the Whites firmly in the hunt as the opening leg of their play-off semi-final ended all square.
Charles pounced to cancel out Barnsley’s opener from Nicky Cadden as Ian Evatt’s men trailed for less than five second-half minutes in the University of Bolton Stadium sunshine.
It was another vital intervention from the Whites’ leading scorer as Wanderers made sure they will head into next Friday night’s return leg knowing that any win will take them to a Wembley final and possibly 90 more minutes from promotion.
That won’t be easy against a savvy Barnsley side, who underlined why they had finished fourth in the League One table with a polished away performance.
But Wanderers think there’s more to come, and having avoided defeat on a tense afternoon when they weren’t at their best, they still have every chance of a second Wembley visit in two months.
With half-a-dozen players returning after a breather in Wanderers’ final league game, there was no shortage of energy in the Whites’ early efforts in search of an opening goal.
A corner inside the opening few minutes fizzed across the face of Barnsley’s goal before Elias Kachunga picked out Charles with a low cross which the striker hit just wide with a first-time shot on the turn.
George Johnston then saw an effort blocked in front of goal following an early corner as Wanderers made the early running.
But it was cagey stuff as neither side wanted a repeat of Wednesday's outcome and after former Wanderers’ midfielder Luca Connell had tested James Trafford with a long-range effort, the visitors took a grip before the break.
Adam Phillips, who scored in the Tykes’ FA Cup win at the UniBol in November, sent a typically well-struck drive just over the top from 25 yards.
And Trafford - giving a fitting performance on his last home appearance - then had to make a fine block to deny Slobodan Tedic as the Wanderers’ keeper stuck out a left hand as his fellow Manchester City loanee looked to dink the ball home.
As in the first half, Wanderers started the second with more of the ball but with their passing game not in top gear it was hard to find gaps in the Barnsley defence.
The visitors were happy not to over-commit but then get men forward whenever they could and with just over an hour gone they grabbed the lead.
Wanderers were forced to concede a corner and when the ball dropped to Cole at the far post, he laid it off for Nicky Cadden to drill home a low shot from the edge of the box.
Evatt responded with a double change from the bench and his side reacted perfectly, too, to level within four minutes.
Randell Williams provided the width and the driven low cross into the six-yard area where Charles showed his poacher’s instincts to pounce on a parry from keeper Harry Isted and steer the ball home with his knee.
Suddenly the tie burst into life and as Barnsley replied Trafford was called into action to make another crucial save, spreading himself to smother an effort from Bobby Thomas.
But with a fantastic crowd behind them, and playing with a greater freedom of their own, Wanderers enjoyed their most threatening spell of the game as they worked the ball well into wide positions and asked questions of the Tykes’ defence.
And the Whites could have taken a lead to Oakwell from the last real chance of the game as Conor Bradley fed the ball into Nlundulu, whose side-footed effort from eight yards out was blocked to send the sides back to South Yorkshire level and with everything to play for next Friday night.
Wanderers: Trafford; Toal, Santos, Johnston; Bradley, Morley, Sheehan (Lee 65); R Williams; Dempsey; Charles (Adeboyejo 77), Kachunga (Nlundulu 65). Substitutes: John, MJ Williams, Thomson, Jerome.
Barnsley: Isted; B Thomas, Andersen, Kitching; Connell; Williams, Philips, Kane, Cadden; Tedic (Norwood 81), Cole (Watters 81). Substitutes: Collins, Russell, Norwood, Benson, L Thomas, Larkeche, Watters.
Referee: Andrew Kitchen
Attendance: 23,450 (2,093)