Rovers took an early lead through Danny Graham’s back post header, but McDermott equalised with a spectacular effort just after the hour mark.
For Dale’s first home pre-season friendly, Josh Lillis was in goal, with a back four of Andy Cannon, Niall Canavan, Jimmy McNulty and Scott Tanser. Joe Rafferty, Jamie Allen and Callum Camps started in midfield, with Donal McDermott, Ian Henderson and Calvin Andrew lining up in the front three.
Possession in the early stages belonged to Dale, with McDermott in particular looking lively. However, it was the visitors who took the lead in the 11th minute against the run of play.
Elliott Bennett crossed from the right flank to Graham at the back post, who headed the ball back across goal to open the scoring.
The goal gave Rovers confidence and they began to wrestle possession back from Dale, with Liam Feeney forcing Lillis into a comfortable save from distance.
Lillis was forced into a much more difficult save moments later, when Anthony Stokes’ cross was headed goalwards by Scott Wharton. Lillis dived to his right to turn the header away, but Canavan’s clearance was poor. Fortunately for the Dale centre back, Bennett’s shot was well over the crossbar.
McDermott looked most likely for Dale, and he gave the Rovers defence something to think about when he picked up on a loose ball and ran towards goal, but his right foot shot was dragged wide of the far post.
A drinks break midway through the half gave Keith Hill the chance to make a change tactically, with Rafferty moving to right back and Cannon moving further up the right flank.
McDermott’s corner was headed narrowly over by McNulty, before the Irishman found Henderson on the edge of the area. The Dale skipper was short on space but dug out an effort which was held by Scott Steele.
Lillis was called into action twice before the break, firstly through goalscorer Graham after his strike partner Stokes found him with a knockdown. Graham tried to curl one around Lillis, but the Dale stopper palmed the effort away before Stokes had an effort blocked out for a corner.
Stokes then turned a Jason Lowe cross towards goal first time, but Lillis was comfortably behind it to make sure the deficit was just one heading into the break.
The opening fifteen minutes of the second half were quiet, with the only two efforts on goal coming from McDermott. Firstly, his low shot across the face of goal skidded past the far post, before a chipped effort from Henderson’s pass from comfortably saved.
The roles were reversed just after the hour mark when McDermott found Henderson with a through ball, but Steele saved Henderson’s one-on-one effort with his legs.
However, there was nothing Steele could do a minute later when Dale equalised thanks to a wonderful strike from McDermott. Rafferty was brought down on the right flank, and McDermott whipped the resulting free-kick into the far top corner from an acute angle.
It was a deserved goal for McDermott who had been involved in all of Dale’s good attacking play, and he almost doubled his tally a minute later. Cannon won the ball back high up the right side, allowing McDermott to carry it forward and send a fizzing effort towards goal. Steele didn’t seem to know much about it as the ball cannoned back off him and clear.
It would be McDermott’s last contribution as he was withdrawn inside the final 20 minutes, along with Andrew and Henderson. On came Reuben Noble-Lazarus, Joe Bunney and first year scholar Aaron Morley.
James Hooper replaced Camps with ten minutes remaining, whilst former Dale loanee John O’Sullivan came off the bench for Rovers.
Cannon and Stokes both fired efforts over for either side, but it was Bunney who the best chance of a winner with three minutes to go. Morley found his fellow substitute with a neat pass, but after working it onto his left foot, Bunney fired over the crossbar.
The game ended all square in what was an evenly matched contest. Dale welcome another Championship side to Spotland on Saturday, with Wigan Athletic coming to town.
Dale: Lillis, Rafferty, Tanser, McNulty, Canavan, Andrew (Bunney 73), McDermott (Noble-Lazarus 73), Allen, Cannon, Camps (Hooper 80), Henderson (Morley 73).
Subs: Dieng, Noble-Lazarus, Hooper, Barry-Murphy, Bunney, Morley, Kearney.
Blackburn: Steele, Lowe (Henley 64), Hendrie (Doyle 66), Ward, Wharton, Feeney (Guthrie 45), Akpan, Lenihan (Byrne 45), Bennett, Graham (O’Sullivan 80), Stokes.
Subs: Fisher, Henley, Guthrie, Byrne, Doyle, Nyambe, O’Sullivan, Raya.