From Vintage Patterns:
"Simplicity Pattern 4981 Vintage Mens Sports Shirt dated 1954. This includes; Man's Sport Shirt: This casual shirt features a convertible collar which may be worn open at the neck or closed. The shirt back is gathered and joined to a yoke which extends to the front in a forward shoulder seam. The pointed collar is featured in both views. In view 1 the long sleeves are pleated to buttoned wristbands. Pocket and collar are accented with saddle stitching. View 2 short sleeved shirt has an additional pocket sewn to right front."