Changes for 2024:
https://www.espn.com/mlb/story/_/id/39161682/mlb-competition-committee-tinkering-pitch-runners-lanes
• With men on base, pitchers will have 18 seconds instead of 20 to begin their motion to home. However, there won't be any changes to the clock when the bases are empty. Hurlers will still have 15 seconds to begin their delivery in those situations. According to the league, pitchers began their deliveries with an average of 7.3 seconds remaining on the 20-second timer in 2023.
• Barring an injury, a pitcher who begins to warm up at the start of an inning will now be required to face at least one batter. Previously, they could be replaced during or after warmups. The league said there were 24 instances last season where the pitcher that warmed up between innings was replaced before throwing a pitch -- adding approximately three minutes of dead time.
• Mound visits will be reduced from five to four per game as the league said they rank among fans' least favorite events in baseball. Teams averaged only 2.3 mound visits per game in 2023 while, according to league data, 98% of games last season would not have exceeded a limit of four visits.
Umpires will permit defensive players to signal for a mound visit without actually visiting the mound to help improve pace of game there, as well. Teams will still be awarded an extra mound visit for the ninth inning if they've used four after eight innings.
• The pitch timer will now reset after a dead ball as soon as the pitcher is given a new one and play is set to resume. He no longer has to be on the mound for the clock to reset, preventing the pitcher's ability to delay a restart by walking around the edges of it.
• During pitching changes, if the clock is under two minutes as the reliever exits the bullpen and onto the warning track, it will reset back to 2:00 rather than 2:15 as it did last year.
• The league withdrew a proposal to reset the pitch clock as soon as a batter calls a timeout. Umpires will continue to use their judgment as to when the clock starts up again.