Dumbarton lost out to a late penalty as Aberdeen scraped through their Scottish Cup fourth round tie at Pittodrie on Saturday.

Sam Cosgrove slotted home a late spot-kick, but Jim Duffy’s men left with their heads held high and counted themselves unlucky that they never forced a replay.

Sons were cheered on by 328 travelling fans who had made the long trip north and looked to frustrate the hosts who would first threaten after a quarter of an hour.

Morgyn Neill and Ryan McGeever were solid all afternoon and, despite being only 23 and 25 respectively, showed real signs of leadership and superbly marshalled teenage full-backs Lewis Crawford and Rico Quitongo through the game, who didn’t look out of place themselves.

The centre-back duo combined to keep out a low shot before Dylan McGeouch, who signed for the Dons last week from Sunderland, forced Conor Brennan into his first save of the game as he comfortably held from the former Celtic youngster.

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Set pieces were the closest that the Premiership side came to scoring throughout the afternoon, with Cosgrove, who has this week been linked with a multi-million pound move to New York Red Bulls, glancing a header over the bar before Ash Taylor was next to nod over.

There were few efforts for Dumbarton who were quite happy to sit back and soak up the Dons pressure. Space did open up for PJ Crossan in the opposition half, but he blazed a shot over as the ball sat invitingly up.

Northern Irish International Niall McGinn was next to try his luck for Aberdeen after smart link up play on the left involving a trio of red shirts but lashed his effort wide.

As the half came to an end, Crawford then had to be aware to block Bruce Anderson’s shot and Sons were half-way to securing a replay.

The hosts came close to scoring on the hour mark as Brennan teamed up with the post to keep out Taylor’s downwards header.

There were a few more openings appearing for Dumbarton as Aberdeen looked to get the tie over on the day – Stefan McCluskey was having success on the left-hand side with a couple of crosses just out of reach of the onrushing Ruaridh Langan.

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Despite all the possession, there were few shots on target from Derek McInnes’ men, although Brennan did react quickly to push away Anderson’s shot before he rushed off his line to put off the same man after he had spilled Funso Ojo’s long range effort.

But, just when it looked like Dumbarton were going to secure a replay, referee Gavin Duncan pointed to the spot in the 85th minute as Cosgrove went down under the challenge of Quitongo.

The English striker dusted himself down and scored his 21st of the season to break Sons hearts and set the Dons up for a last 16 tie with Killie.

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