In the beginning of the film, Artie mentions that he "feels 10 years younger" than he is, and "looks 10 years younger than that." Diane responds by mentioning that if he's 38 years old, he should paint the house. This means that Artie is 58 years old. Later, Alice says that she had Harper when she was 26, and because Harper is 12, Alice is 38 at the time of the movie. This means that Artie had Alice when he was 20, not 23 as he says.
When Artie is doing play by play for the Braves vs Giants game, he mentions Hudson as the starter for the Braves. When the game is shown on TV it is clearly Derek Lowe who is the pitcher for the Braves.
When grandma, Diane Decker, greets the grandchildren, she kisses them. The lipstick is really light with the first kiss and becomes darker at the end. It should be the other way around so Bette Midler had to re-apply lipstick so that it would show up on film.
During the ice cream cake fiasco scene, Phil comes on screen with a video chat for Alice. Alice rushes over to turn it off and the screen is clean. When Harper and Alice start playing tug of war over the ice cream cake a few moments later (after the boys went to hide under the counter and are no longer running around), the screen has a frosting hand print on it.
At the beginning of the movie, when Artie mentions team names that he gets to announce, one is the "Rancho Cucamonga Quakes." Though that is a real team, they are a single-A team, and would not play against the Fresno Grizzlies, who are a triple-A team.
When Arty is searched by the TSA there are (what appear to be) U.S. Marines behind him to his right wearing desert camouflage uniforms. U.S. Marines are not authorized to wear camouflage uniforms off-base unless authorized by their command(s). Also, from October 2011 through March 2014 Marines did not wear their sleeves rolled up.
Turner's re-creation of the famous Russ Hodges call of the "Shot Heard 'Round the World", is not exactly accurate. He fails to mention that Clint Hartung was on Third when Whitey Lockman was on Second.
Artie mentions a kiss-cam and marriage proposal happening on the scoreboard, which is happening during a conference on the mound. These events typically are shown between innings instead of in the middle of one. And marriage proposals are typically done in the fourth inning, not the ninth.
When at Turner's Speech Therapy, the camera shows Turner with his ear-buds out of his ears hanging on his shirt, and when the Therapy teachers says that it is Turner's turn, the camera pans around to Artie, it comes back to Turner and the ear-buds are in Turner's ears.
Artie gets fired at the end of the baseball season (Early September for Fresno Grizzlies). Then he goes and sees his grandson's little league game (Fall Little League begins in August in Metro Atlanta). (Has to be school year because two older kids have school.) Then he goes and auditions at the X-Games as an announcer (X-Games have never been held in Atlanta).
When Artie Decker drops Barker off at school, the car seat has the seat-belt going in front of the child and not through the car seat itself. This is not the correct way to install the car seat. However, it may not have been as funny if they didn't do it this way.