Jerseys on baseball players usually fit baggy and loose and so you may be concerned with fit. Do MLB jerseys run big? Yes, MLB jerseys run big in comparison to standard t-shirts, but the fit will depend on which jersey type you buy. ... It is important to understand that there are multiple types of MLB jerseys to purchase.

How do I know my jersey size?

MENS JERSEY SIZING

Measure around the fullest part of your chest under the arms for your total chest circumference. If you're on the borderline between two sizes, order the smaller size for a tighter fit or the larger size for a looser fit.

Do Mitchell and Ness baseball jerseys run big?

The Mitchell and Ness Authentic jerseys fit very slim – I had to size up. If you prefer a loose fit, you may need to size up two sizes. Mitchell and Ness Authentic jerseys use a numerical sizing system instead of the standard small-medium-large sizing that the Swingman jerseys use.