Rodriguez has improved the depth of his slider as well as being able to throw it to both sides of the plate, Evan Drellich of the Boston Herald reports. "It's that pitch that has advanced him a little bit more this spring," said manager John Farrell.
Rodriguez allowed two hits and three walks while striking out six in four scoreless innings Friday, giving him a 2.08 ERA with 13 strikeouts and five walks over 13 spring innings. His performance this spring, coupled with a strong finish to 2016, points to the left-hander being an important piece of Boston's rotation, particularly with the uncertainty surrounding David Price.