The clock was moving. It began ticking the moment Martavis Bryant crossed into the end zone. It continued as Bryant took a knee and began to celebrate by "throwing dice" with Pittsburgh Steelers teammates Antonio Brown and Eli Rogers.

The clock kept moving as Steelers coach Mike Tomlin signaled for a two-point conversion attempt and as quarterback Ben Roethlisberger searched for the play on his armband. Then, as Roethlisberger was getting players in position on the line, it hit zero. Flags flew. The foul: delay of game on the Steelers.

That scene, in the first quarter of the Steelers' 26-9 victory against the Minnesota Vikings, illustrated the impact of the NFL's offseason efforts to improve the pace of games. One of its time-saving tools is an instruction for referees to start the 40-second game clock immediately after touchdowns, effectively limiting the length of celebrations even through restrictions on their content have been relaxed.

Through nearly two full weeks of the season, the result of the league's efforts has been notable. The average time of games has been lower in Weeks 1 and 2 compared to the same time periods in 2015 and 2016, as the chart shows. Of Week 1's 15 games, 10 finished in less than three hours, and no game in Week 2 has gone longer than 3:16. (The numbers do not include Sunday’s 1:05 weather delay in Denver.)

Although it's difficult to unpack the decrease fully in a relatively small sample size, it should be attributed at least in part to changes that commissioner Roger Goodell suggested could shave as many as five minutes off an average time of game. (It reached 3 hours, 8 minutes last season.) The post-touchdown timing we saw Sunday in Pittsburgh is one of multiple factors likely at play. Among the others:

A new 40-second clock after PATs when there are no commercials. Per multiple officials who gave media seminars this summer, the clock begins the moment the kick or two-point conversion is complete. After 40 seconds, officials start a 25-second game clock for the kickoff. So in those situations, no more than 1:05 can pass between a PAT and a kickoff. If the kickoff team isn't lined up when the 25-second clock starts, officials are instructed to put the ball on the ground and be prepared to call delay of game if it expires.

The timing of halftime has been reorganized to minimize what the league referred to as "discretionary" time. A countdown of 13:30 begins when the second quarter clock hits zero and ends when the 25-second clock for the third quarter kickoff begins.

Replays are reviewed in the league's New York headquarters, a shift that over time the league believes will speed up the process. Referees are also permitted to announce the results before the television audience returns, if it is in commercial, rather than wait and cause further delay.

The NFL is more focused on the pace of game -- moving through dead time faster -- than reducing the actual length. But a successful effort would likely affect both.

The reality is that the NFL had seen its time of game creep up nearly six minutes in the past 10 years. (It was 3:02 in 2008.) An anecdotal Vox.com study revealed that game action occurs on roughly 8 percent of an average NFL broadcast, and the Wall Street Journal once estimated there to be action in 11 minutes of a three-plus-hour game.

The NFL isn't going to change its product fundamentally with this initiative, but it might well prove successful in shaving down some of the most obvious factors in the slowdown. The Steelers' penalty Sunday made the game a bit longer, but it should now serve as a valuable incentive to keep a better eye on the clock in future situations for both them and any other team watching.

In this case, Tomlin scrapped his plan for a two-point attempt. Rather than try for it from the 7-yard line, after a 5-yard penalty, he sent out place-kicker Chris Boswell for a 38-yard extra point.

The impact of some segments of this policy will be difficult to measure. The NFL is experimenting with split-screen commercials during replays, which could help bridge interest from the television audience, and is also minimizing the recurrence of two commercial breaks between scores and the first play from scrimmage after the kickoff. But the early numbers we can access are in, and they're encouraging. We shall stay tuned.