I've been struggling with bench recently and have discovered that if my spotter supports the right side of the bar, I'm able to complete the set with considerably greater ease than if I did it on my own.
This leads me to believe that my bench progress is being hampered by a difference in strength or muscle development between my left and right sides, possibly caused by an old injury.
I am not exactly sure which muscle is the weaker. I've noticed mild pain in my right shoulder but it doesn't seem to be enough to hamper my bench.
What sorts of exercises can I do to better equalize the strength between my left and right sides?