Dundee fell to a disappointing defeat at Airdrieonians thanks to a late Rhys McCabe penalty.
That was after Lyall Cameron saw a spot-kick of his own saved by home keeper Josh Rae in the second-half.
The Championship side took all three points in Viaplay Cup Group E with the 1-0 home success.
Changes
Tony Docherty made three changes with Zach Robinson and Owen Beck nursing knocks and Max Anderson dropping to the bench.
That saw Malachi Boateng make his full debut, Josh Mulligan come in and Jack Wilkie make his first-ever Dundee start at left-back.
The visitors enjoyed the majority of possession in the first half but struggled to break down the home defence.
In fact it was the Diamonds who created the best chances of the first 45, McCabe denied at the far post by Jon McCracken before Gabby McGill headed over from the resulting corner.
Dundee’s best efforts saw Cammy Kerr have two goal-bound shots blocked and then a Lyall Cameron effort from six-yards also blocked by some frantic home defending.
Pineda arrival
The second half began in similar fashion before Docherty called for new boy Pineda to replace Rudden up front with half-an-hour to go with big cheers from the away support.
Immediately the Dark Blues got a lift and minutes later had a penalty kick after Scott Tiffoney was taken down by home goalie Josh Rae.
Rae made up for that, though, by pushing Lyall Cameron’s spot-kick around the post.
Mexican Pineda brought an energy to the Dundee frontline, however, there was late heartbreak to come.
Wilkie had put in a strong show at left-back but was adjudged to have pushed his man in the area and referee Colin Steven pointed to the spot.
Airdrie player-manager McCabe stepped up to send McCracken the wrong way and put his side top of Group E, three points in front of Dundee.
Dundee: McCracken 7, Kerr 6, Shaughnessy 7, Ashcroft 7, Wilkie 6, Boateng 7, Mulligan 6, Cameron 5 (Robertson 69, 6), Tiffoney 6, McCowan 7, Rudden 6 (Pineda 59, 7).
Subs not used: Legzdins, Sharp, McGhee, Byrne, Anderson, Graham, Lamb.
Star man:Â Lee Ashcroft