The game kicked off in torrential rain and Lee Miller won a free kick in a dangerous position after only two minutes. Mulgrew fired in a decent effort forcing Jellema to palm the ball away from the danger area. Three minutes later the home side won a similar free kick and they won the opening corner of the match as it was deflected wide off of Mulgrew. Aberdeen then took an eternity to clear their lines and were forced to concede a second corner before Langfield gathered and set up a Dons attack.
Maguire had his effort blocked before Jellema gathered to prevent a corner. Aberdeen then took the lead in the 8th minute when Aluko broke well and found Chris Maguire with his pass. The youngster cut inside and his shot was steered past the keeper by Lee Miller. Aberdeen won their first corner in the 12th minute but Scott Severin fired an effort well over to end the danger. Aberdeen were on top at this stage and the home side were forced to defend deep as Aberdeen looked for a decisive second goal.
Aluko won another free kick in the 16th minute and although the initial threat was cleared, the ball fell to the Englishman and his effort was cleared off the line by Hill. Two quick corners were won around the 20 minute mark but both efforts were comfortably cleared. The Dons continued to pound the Alloa goal and Campbell collected the first yellow card of the game in the 27th minute as the home side started to feel the pressure. In the latter stages of the half Aberdeen started to lose their way as Alloa looked to force an equaliser.
The home side went close to achieving this in the 38th minute when a corner kick caused problems with a chance for Townsley before Grant turned the ball over the bar. A minute later they were rewarded when they won a penalty kick despite the fact that Hill had already turned the ball into the net. The play had already stopped before this as the match official had apparently spotted the tug of a shirt by Scott Severin.
Severin collected a yellow card for his troubles and the play was held up because of ticker tape that was thrown on to the pitch. Andy Scott was unaffected by the long delay and calmly fired the ball past Jamie Langfield to level. Aberdeen had no one to blame but themselves as they went from a comfort to calamity. Aberdeen had one last chance as Buist conceded a free kick and collected a yellow card in the last minute. The ball was fired in and Buist was forced to concede a corner but Alloa survived the threat to go in level at the break.
Mackie replaced de Visscher at the interval as Aberdeen looked to regain the lead straight from the off and Foster went close with a fierce shot in the 47th minute that went inches wide. Alloa were proving that they were not there to make up the numbers as Mulgrew was forced into a last gasp challenge to deny Wilson in the 50th minute. Aberdeen were back ahead in the 57th minute when a ball over the top found Aluko who went one-on-one with the keeper and finished the move with style to score what would ultimately be the winner.
Aberdeen looked to extend their lead a minute later but Lee Miller was flagged offside in what looked a very tight decision. Townsley was cautioned on the hour mark after a reckless challenge on Gary McDonald. Mulgrew in turn fired in a teasing free kick, but there were no takers. Good possession play from the Dons had the Alloa defence at sixes and sevens but once again the Dons failed to find the finish. Alloa won their first corner of the second half in the 67th minute and not for the first time the referee got a decision wrong as he awarded the home side a second corner when it clearly came off Townsley.
Fortunately Aberdeen defended the set play well and no harm was done. Two minutes later Scott went close to adding his second as he tried to latch on to a cross. Another corner in the 73rd minute caused problems for the Dons as Langfield missed the ball before it was eventually turned over the bar by the home side. Once again Aberdeen had taken their foot off the pedal and Alloa threatened to level for a second time. McLune completed the bookings of the Alloa back four after he took down Aluko. The resultant free kick saw Mackie hit the woodwork as Alloa lived dangerously.
Aberdeen had a great break in the 77th minute but referee Nicholls decided to pull play back for a free kick for the Dons. Foster was cautioned in the 81st minute for an innocuous challenge that produced a free kick, which saw Alloa once again go close. Aluko was felled for the umpteenth time a minute later and if Fosters challenge merited a yellow card then surely Townsley's indiscretion deserved the same. Fortunately for the defender he was spared what would have been a sending off. Six minutes from the end Alloa went even closer as Ferguson headed wide from six yards.
Mulgrew conceded a free kick wide on the right in the 87th minute but the Dons cleared and attempted to counter. There was certainly a sense that the Dons were hanging on to their lead but Aluko was scythed down again by McLune a minute later and again the referee kept his card in his pocket. From the free kick the keeper was forced to bundle the ball round the post as Mulgrew threatened to get on the score sheet. In injury time the referee found his cards again when Scullion, who had not been booked, was cautioned after downing Maguire. The Dons eventually held out to move into the fifth round draw tomorrow.