Umpires do an excellent job but each are far from perfect. But if an umpire is consistent throughout an entire game with his strike zone location, more times than not both teams will agree it was a fairly called game. As a method to ''grade'' an umpire's performance, MLB uses a high-tech Zone Evaluation (ZE) System (an upgrade from QuesTec) to monitor the accuracy of calls. They use several cameras which send their video to one computer to determine pitch location.

The strike zone is defined as the area over homeplate the upper limit of which is a horizontal line at the midpoint between the top of the shoulders and the top of the uniform pants, and the lower level is a line at the hollow beneath the kneecap. The strike zone shall be determined from the batter's stance as the batter is prepared to swing at a pitched ball. But as all gamers know, that's not always the case.

Elite veteran players are more likely to be the beneficiary of a border line pitch than a youngster, which is part of the game and accepted. The same goes for veteran pitchers, as umps will often slightly expand the zone for the greats on the mound. But how far will an umpire expand the zone in certain situations? And how is the strike zone interpreted by each? Like players, every man calling balls and strikes has his own style and manner in which a game is called. To the MLB wagering fans there's two types of umps. There's hitter friendly and pitching friendly men in blue. If you bet on MLB, it's important to know the ump's nature, particularly when investing in game 'totals'.

With the season still in its first month, let's reflect back to 2008 stats to get a grasp on which umpires favor 'over' and the ones prone to call a game 'under', as a key tool that'll help build your BetPhoenix bankroll throughout the 2009 MLB marathon season. Let's start with last year's top-five hitter friendly umps, that made 'over' supporters happy, followed by the one's pitchers and 'under' players like calling games.

1 - Angel Campos - O/U 18-5 (78.3%) 11.6 runs were scored per game with Campos behind the plate with 6.6 batters per game reaching first via base on balls. 14.8 batters per game were called out on strikes

2 - Gary Darling - O/U 23-11 (67.6%) 9.9 runs were scored per game with Darling behind the plate with 6.4 batters per game reaching first on walks. He rung up 12.9 batters per game.

3- Jerry Meals - O/U 23-12 (65.7%) 9.9 batters crossed homeplate per game with Meals calling balls and strikes with 6.5 free passes to first. He called 13.5 batters per game out on strikes.

4 - Jim Reynolds - O/U 21-11 (65.6%) 10.3 runs per game were posted when Reynolds wore the mask. 6.1 hitters per game reached base via balls, while 13.0 were sat down on strikes.

5 - Tim Tschida - O/U 21-13 (61.8%) 9.9 runs were plated per game with Tschida behind the dish with 7.4 hitters awarded first base on balls. He called out 14.5 batters per game on strikes.

Last year, the average number of runs scored in the NL was 9.42 and 9.80 in the AL. The MLB average number of walks was 6.6 per game, while 6.73 strikeouts were recorded. Each of the above umpires were pretty close to the league average in walks. But notice, all were nearly double in the MLB's strikeout average category. That indicates each has a small strike zone that forces pitchers to throw over the heart of the plate, which manufactures a lot of hits converted into runs. And as you see, if the batter doesn't make contact, all of the above umps are not hesitant to punch them out. Now to your 2008 pitcher and 'under' friendly men in blue.

1 - Bob Davidson - O/U 10-23 (69.7%) 8.0 runs per game were scored when Davidson was calling the count. He allowed 7.3 walks per game, while batters were retired via strikes 13.8 times.

2 - Ron Kulpa - O/U 10-22 (68.8%) 7.8 runs per game crossed the plate when Kulpa wore the mask. He warranted 6.2 bases on balls and rung up 15.1 hitters per game.

3 - Mike Estabrook - O/U 7-15 (68.2%) 8.2 runs per game were put up when Estabrook was calling balls and strikes. He allowed 6.3 walks and 13.0 batters per game went down on strikes.

4 - Marty Foster - O/U 11-21 (65.6%) 8.8 runs scored per game when Foster was behind homeplate. He allowed 6.6 free passes to first on balls, while 13.9 batters sat down on strikes per game.

5 - Angel Hernandez - O/U 11-20 (64.5%) 7.3 runs per game were plated when Hernandez was calling a game. He issued 6.3 bases on balls and 12.7 hitters per game recorded outs by way of strikes.

It's interesting to note, other than the obvious lesser runs scored per game, these umpires have similar stats in walks compared to the first group. Outs recorded by strikes are remotely lesser, but seemingly not by a margin significant enough to account for the huge difference in 'total' records between the two groups of blue. So why do the above five umps have stats favoring 'under'? There's no definite answer or reason, which is why betting baseball can be tricky, though numbers don't lie and it's no coincidence the difference between 'under' umpires and 'over'.

So when doing your homework, and before investing in a game's 'total', research who's calling balls and strikes and factor that into your play. In addition to the general stats provided within this article, there's a wealth of information on every umpire in the game, including valuable trends for all the games if you wager on MLB action. So visit the BetPhoenix MLB odds, know your blue and don't go looking!