The first of three Saints trips to the end zone that were called back. (Twitter: NFL)

To end the first half Monday night, the New Orleans Saints thought they scored a touchdown on three separate occasions. They ended up with zero points and headed into the locker room trailing the Detroit Lions 21-3.

Here's what happened.

Driving at the tail-end of the first half, Drew Brees hit Brandin Cooks deep down the field. Cooks made a remarkable grab and dove into the end zone. The official on the field raised his arms to signal a touchdown for the Saints, even though Cooks was clearly touched by a Lions player and his knee touched down well before the goal line.

After an automatic review, the play was overturned and the Saints were given the ball at the 1-yard line. Why did the official give the Saints a touchdown in the first place? Who knows.

On first-and-goal, the Saints were stuffed. On second-and-goal, Tim Hightower found the end zone for a touchdown. But the officials flagged the Saints for an illegal formation, negating the touchdown. The Saints' second touchdown was taken off the board.

Now backed up near the 5-yard line, the Saints handed the ball to Hightower again on second-and-goal. Hightower got stopped short of the goal line at the 1-yard line. The Saints turned to Hightower again on third down, but he was shut down by the Lions at the line of scrimmage.

The Saints burned the clock so that three seconds remained, calling a timeout to discuss their fourth-down play. Then, just before Brees called for the fourth-down snap, the Lions called timeout and the officials stopped the play.

The only problem? The Lions had no timeouts remaining.

As a result, the down was replayed and the Lions weren't penalized for trying to use a fourth timeout. In other words, nothing happened after the brief stoppage of play. 

So, on fourth down, Brees found Marques Colston in the end zone for a touchdown. Finally, the Saints scored a touchdown.

The Saints hit another snag, though. The officials threw a flag on the play for an illegal receiver downfield. The drive ended on downs and so did the second quarter. Halftime. 

And that's how the Saints scored three times and came away with zero points.