Another stunning Lions win might be the end of the line for Mike Smith

Confirmation that this season indeed might be different for the long-suffering Detroit Lions and that Mike Smith's days in Atlanta are numbered both came within the span of about a half-hour early Sunday.

After racing out to a 21-0 lead in London, the Falcons managed to bumble their way into allowing Detroit a game-winning shot. And after a bizarre sequence of events, the Lions took advantage via a 48-yard Matt Prater field goal on the game's final play, which gave them a stunning 22-21 victory.

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Despite doing almost nothing right in the second half, Atlanta still clung to a 21-19 lead late -- the Lions settling for 20- and 22-yard field goals certainly helped.

And the Falcons were on the verge of icing away their third win of the year after Julio Jones picked up a first down at the two-minute warning; the Lions had just one timeout left. But a holding call on an ensuing 2nd-and-9 stopped the clock (even though Detroit declined the penalty) and Smith's team doubled down by firing an incomplete pass on 3rd-and-9. 

Instead of handing the ball back to Detroit with mere seconds on the clock, Atlanta punted at the 1:46 mark, leaving Matthew Stafford ample time to orchestrate a drive.

He did just that. Shaking off an uneven first half, Stafford fired a pair of second-half TD passes and then marched the Lions 68 yards in 1:34, setting up Prater for a field goal try. 

But even that was not the end of the drama. Prater pushed a 43-yarder wide right ... only to be saved by a delay of game penalty. He then drilled another attempt from five yards further back, moving the Lions to 6-2 on the year.

It's worth noting that on Detroit's previous drive, the officials appeared to miss an obvious delay of game just before a Stafford completion. Regardless, this was the second consecutive improbable win for the Lions, who stormed back from 23-10 down in the final four minutes last week to beat the Saints.

And, as in that comeback, they pulled off this one despite Calvin Johnson standing on the sideline in street clothes. Reggie Bush, Brandon Pettigrew, Joseph Fauria and Eric Ebron all joined him as non-participants Sunday, leaving little beyond Golden Tate and a collection of role players for Stafford.

Tate again shouldered most of the load, hauling in seven catches for 151 yards and a touchdown -- his most important catch a 32-yarder to open that decisive final drive. Rookie RB Theo Riddick made a critical play seconds later, somehow coming up with a one-handed grab to take the Lions across midfield. 

One more Stafford completion, this time to Jeremy Ross, put Detroit into FG range. Prater did the rest.

Of course, he may never have had a shot without a bit of a coaching meltdown from the Falcons' staff. Smith already found himself on the hot seat, a disappointing 2-5 start following last season's 4-12 finish. 

While the holding call just past the two-minute warning was a bit of bad luck, the decision to then throw the football on third down will haunt Smith all the way back across the pond. Simply taking a knee and punting there would have drained the clock down to about one minute, severely hampering the Lions' final drive.

Making matters worse, the Falcons twice saved Detroit from having to rush its kicking unit onto the field for Prater's attempt. The Lions, operating sans a timeout, handed off to Joique Bell with 34 seconds left and then Smith rather inexplicably called a timeout after that play ended; Paul Soliai then was called for defensive holding on the next snap, yet another Bell run play on a 3rd-and-9. 

Between the mounting losses and this latest Falcons collapse, it's extremely hard to see Smith sticking around much longer. 

The situation is far more jovial for Lions head coach Jim Caldwell, whose team is winning games it absolutely would have lost in past seasons. None of those victories have been more dramatic or shocking than the one Detroit grabbed Sunday.