Kumar Sangakkara reached 10,000 Test runs as Sri Lankan wickets toppled around him on the opening day of the second Test against Australia at the Melbourne Cricket Ground, leaving the tourists at 79-3 at lunch. Sangakkara unfurled a glorious cover drive boundary off Mitchell Johnson in the final over before the break  to bring up the milestone in his 115th Test match. It came in his 195th innings -- the same point at which batting greats Brian Lara and Sachin Tendulkar notched the feat. Australia dominated the opening morning of the Test, after Sri Lanka won the toss and batted before a huge Boxing Day crowd. The Australians were buoyed by the availability of skipper Michael Clarke after a strained hamstring and made inroads into the Sri Lanka batting top order under sunny skies. At lunch, Sangakkara was unbeaten on 43 with Thilan Samaraweera on 10. The Australians opened with new pace pair Johnson and debutant Jackson Bird and soon had the Sri Lankans under pressure. Bird captured his first Test wicket with his 10th delivery when he moved the ball away from left-hander Dimuth Karunaratne and the outside edge was taken by Matthew Wade for five. Hobart centurion Tillakaratne Dilshan fell three overs later when Johnson got one through his defences and cannoned into the off-stump for 11, leaving the tourists a shaky 19 for two. It got worse for Sri Lanka when Mahela Jayawardene was out three balls after first-hour drinks for three, continuing a dismal scoring series for the skipper. Peter Siddle moved one off the pitch and enticed an edge off Jayawardene\'s bat to give Wade his second catch and leave the Sri Lankans 37 for three in the 13th over. Sangakkara hit his straps nearing lunch, reeling off 15 runs from four Johnson deliveries with three consecutive boundaries and a three. The elegant left-hander received a sustained ovation from the large MCG holiday crowd for reaching 10,000 Test runs.