The Nationals selected the contract of three prospects Thursday evening, adding them to the club’s 40-man roster and protecting them from being taken away in next month’s Rule 5 draft.
None of the three players — infielder Chris Bostick, catcher Spencer Kieboom and left-hander Nick Lee — rank high on the Nationals’ top prospects list, but all had been in the organization long enough to require roster protection.
Bostick, one of two players the Nationals acquired from the Rangers last winter for left-hander Ross Detwiler, impressed in his first season with the organization. The 22-year-old infielder hit a combined .