What a bad beat! Last-second Lightning goal costs under bettors.

As far as bad beats go in sports gambling, it was pretty brutal.

With one second left, the Tampa Bay Lightning scored what looked like a harmless empty net goal in a 4-2 victory over the Washington Capitals in Game 4 of the Stanley Cup Eastern Conference finals on Thursday.

To gamblers, it was anything but harmless.

The over/under on total goals scored for the game was set at 5.5 or 6, depending on the sports book, USA Today reported.

Those taking the under were on the verge of winning whatever they bet. That's when Anthony Cirelli ripped the win away from under bettors with an empty net goal with one second remaining.

To make matters even more gut-wrenching, television broadcasters calling the game announced it was potentially offsides.

It wasn't, and the goal cost under bettors the win. Those that got in on the action with an over/under set at 6 ended up pushing, or tying the bet.

The United States Supreme Court overturned the federal ban on gambling earlier this week, instead leaving it up to individual states to govern.

The Lightning return to Tampa for Game 5 even in the series at two games apiece with the Capitals.

This story was originally published May 18, 2018 at 12:59 PM with the headline "What a bad beat! Last-second Lightning goal costs under bettors.."