SCOTTSDALE, Ariz. -- The Arizona Fall League has proven to be an excellent laboratory for Major League Baseball, and the 2014 season, which kicked off on Tuesday, will be no different.

A year ago, instant replay was tested in the Fall League and then implemented in the 2014 regular season. This time around, initiatives developed by Major League Baseball's Pace of Game Committee will be tried on for size.

The AFL began experimenting with a host of time-saving measures, including restrictions on hitters stepping out of the batter's box between pitches, limits on the time allowed between innings and for pitching changes, a change in how intentional walks are issued, reducing the number of conferences, and the modification of existing rules on the allowable time between pitches.

Also in league-wide effect was the one mandating a hitter keep one foot in the batter's box at all times. There are several exceptions to that rule, including a foul ball or a foul tip, but it did seem to have an impact. The afternoon games in Surprise and Glendale finished in 2:33 and 2:39, respectively. A total of 21 runs were scored in those two games, so it wasn't just a matter of efficient pitching. The night game took 2:56, thanks largely to a long and sloppy first inning, bringing Tuesday's average to 2:42. The AFL average time of game in 2013, by comparison, was 2:51.

The opening game at Salt River Fields on Tuesday night was the first to utilize a pitch clock, set at 20 seconds, the time allotted for a pitcher to throw each pitch. The punishment for going over the time -- an automatic ball -- was not enforced in this game, though pitchers did a solid job of adhering to the 20-second limit in this first test.

"It was a little different," said Diamondbacks prospect Archie Bradley, who started the game for the Salt River Rafters. "With no one on base, it wasn't a big deal. Even though you know there's really no penalty right now, it definitely added something a little different, having to think about something else. I know for both times a runner was on second base, having to communicate with my catcher and try to figure out what pitch to throw, you're peeking at the clock and realize you have five seconds to make a pitch, it's definitely a little different."

There's a lot on a pitcher's plate, Bradley explained, especially once a runner has reached base. Adding in the worry about the pitch clock definitely made it tougher to pay attention to the task at hand.

"It's a lot to think about," Bradley said. "As a pitcher, you're worried about the running game, what pitch to make. Now you have to worry about the clock.

"Out of the stretch, when I'm worried about making a pitch, I'm looking to see how much time I have. For us, when we're focusing on the glove, trying to focus on executing a pitch, it takes a little focus away from what your main point is, trying to get that guy out."

There was a little more confusion over the between-inning break rule. A lack of understanding of the two minutes, five seconds limit may have been the cause of the Salt River Rafters and Scottsdale Scorpions both exceeding the time limit early on. When the rule was re-communicated on the field, the time between innings did improve as the game went on. With Tuesday being viewed as a dry run, the punishments weren't enforced.

"The in-between innings thing is going to be a little hard to adjust to as well," Bradley said. "Only having two minutes puts stress on us and the catcher, and everyone to get out there, get loose and find the strike zone again in your warmup pitches. That's not something we're used to."

All of these experimental rules will be in full effect at next Tuesday's game at Salt River, the one field where the pitch clocks will be in place. If a hitter doesn't comply to the between-innings rule, which states he must be in the batter's box by the one minute and 45 seconds mark, the umpire will call a strike. If the hitter is ready but the pitcher doesn't deliver a pitch by two minutes and five seconds, the umpire will call a ball.

Some of the rules were in full effect, not just in Tuesday night's game, but league-wide, as the Fall League began its 23rd season. Intentional walks didn't have to include the pitcher lobbing four balls outside of the strike zone, with the manager signaling to the home-plate umpire that he wanted to walk the hitter instead. It didn't come into play on Tuesday and with the AFL serving largely as a developmental league, this is one rule that is unlikely to have much of an impact this fall. As the events of Game 4 of the NLDS between the Giants and Nationals showed, when Aaron Barrett's attempted intentional walk offering went to the backstop, there might be those who would object to removing that variable from the game.

One other rule, the timeout limitation, will only be implemented at Salt River. In those games, each team will be permitted three "timeout" conferences covering any meeting involving pitchers and catchers, managers, coaches and batters. Timeouts during pitching changes and those that result from an injury or other emergency will not be counted toward the limit.

All of these initiatives are very much in the early experimental phase, with the ideas being tried coming after just one meeting of the Pace of Game Committee. It's unclear how many of these rules, if any, will be instituted in Major League Baseball in the future. But the committee felt it was better to try them out now, perhaps less than fully fleshed out, than wait another year for the 2015 AFL. This is in contrast to last year's Fall League trial for instant replay, which was certain to be implemented in some capacity the following season.

"I admire the effort," said Cubs president of baseball operations Theo Epstein, who was in Glendale on Tuesday afternoon to watch Cubs prospects on the Mesa Solar Sox play. "It's a real issue and baseball is facing it head on. This is a good place to experiment and see how it works. Something has to be done to improve the pace. I think we're on it and I think we'll have some good talks about it this winter."

Time of play issues aren't the only things being looked at during this year's AFL. Instant replay is being expanded to include everything but balls and strikes. They will also be enforcing the modified "in the neighborhood" rule, where the fielder will be required to touch second base with possession of the ball in order to record a forceout, even in cases where he is attempting a double play.