5 controversial decisions taken by the third umpire 

#1 Nathan Lyon gets lucky with inconclusive evidence rule (2015)

Australia and New Zealand played a historic Day-Night Test at the Adelaide Oval in November 2015. Pink ball, under lights, Test cricket - there was lots of excitement.

New Zealand won the toss and batted first, but could post only 202 and were bowled out on the first day. Australia saw off the night session and reached 54/2 at the end of day 1. However, an all-round effort from all the Kiwi bowlers on the second afternoon (first session of the second day) helped them reduce the Aussies to 116/8. Peter Nevill was still out there and held the key for Australia.

In the second over of the second session, Mitchell Santner (on debut) was bowling around the wicket to Nathan Lyon. A delivery which was on a length and was turning away slightly, Lyon went for the sweep shot and the ball lobbed up off his shoulder (after taking a faint edge) to second slip. The New Zealand fielders were confident that Lyon had edged it, but umpire S Ravi turned down their appeal.

The Kiwis decided to take a review. Nigel Llong was the third umpire. He went through the entire process slowly. The front-on replays looked very close. Hotspot showed a prominent mark on the top edge of the bat. Looking at the replay on the big screen, Nathan Lyon started to head back to the pavilion.

However, to his surprise, after a lengthy deliberation, the third umpire decided to rule it in favour of the batsman. Umpire Llong stated that he has no conclusive evidence to overturn the decision. Hence, Lyon survived. The Kiwi players on the field couldn’t believe it. In fact, Brendon McCullum who is generally a calm person had a length conservation with the on-field umpire.

This decision proved to be very costly as Lyon scored 34 and Nevill scored 66 to take Australia into lead (which was vital). In the end, Australia won the historic Test match by 3 wickets.