If 1st baseman is playing properly he should be off the fist base a good distance in order to cover more territory.
If a ball is hit to him and he is unable to get to first in time the pitcher should cover first base. (On any hit ball to the right side the pitcher should get in habit of moving that direction in order to cover 1st base if necessary.)
On contact the pitcher should move in direction of first base.
The pitcher should run towards 1st base, when approach 1st base he MUST touch inside corner of base. If he runs over base or touches middle he takes chance of collision with runner and possibility of getting hurt.
1st baseman toss ball underhanded to pitcher, tossing ball before pitcher gets to first. Lead the pitcher with the toss. Let the pitcher run under the ball. Pitcher should run past the base, running on the inside to the base.