With the game slipping away from Pakistan when Australia reached 447-5, home wicketkeeper Matthew Wade slogged Yasir into Azhar Ali's helmet as he fielded at short leg and the opening batsman slumped to the ground in pain.
The pacer said that everyone thought the first day/night Test between Australia and Pakistan will end within just 3 days.
Opener Azhar Ali had anchored the innings with 66 in the gloomy conditions, while first-Test hero Asad Shafiq was four not out. Left-armer Steve O'Keefe would appear the logical candidate for a recall, with Jon Holland now sidelined by an ankle injury. In Pakistan's first innings at the MCG, Lyon took 1 for 115 from 23 overs, his figures ballooning as Pakistan chased quick late runs on day three.
Josh Hazlewood got his reward for his nagging accuracy with the wicket of Sarfraz Ahmed for 10, snapped up by Matt Renshaw at first slip.
Pakistan began day two at 4-142 and ended it impressively at 6-310 despite a handful of rain delays cramping both team's rhythm at different stages of the day.
After stumps was called early on day one, there were hopes for more play on Tuesday and Pakistan made hay while the sun was sort of shining. While Warner did it in 59 Tests, Smith has achieved this feat in just 49 Tests, meaning a century in every three Tests.
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Steven Smith's century - his 17th in career and 4th in 2016 - ensured Australia take lead against Pakistan on the fourth day.
Australia's pacemen were unable to garner much from the pitch and were despatched all over the ground as the old ball came to the end of its life.
Smith also said it is likely that another spinner will be included in the squad for the match at the SCG.
"I'm not sure. That's up to the selectors", Smith said when asked if Lyon was an automatic selection for the Sydney Test. Captain Steve Smith's foresight was maybe the best example, anticipating a cheeky ramped shot from the Pakistani batsman at one point and moving to catch, but watching as the ball skewed just beyond his outstretched fingers.
"We were going to play more positively this afternoon and get as many runs as we can but the rain hasn't helped us", he added.