Gallacher finished with a 22-under total of 266. Looking for his first European Tour win since 2004, Gallacher (71) had a nervous start. The 111th-ranked Scotsman had a three-shot lead over Sterne but bogeyed the first two holes while Sterne birdied the second.
The two traded places several times after that, as each struggled in windy conditions. Gallacher then holed a sand wedge on No. 16 from 115 yards for an eagle that gave him a four-shot lead.