Buster's Buzz: Why Nationals' defense will be much better in 2019

What does Machado's deal mean for Harper? (1:10)

Buster Olney sees Manny Machado's $300 million contract as a win for Bryce Harper's free agency. (1:10)

Nationals manager Davey Martinez stopped to chat at the edge of practice field No. 3 the other day in West Palm Beach, Florida, and behind him, coaches swung fungo bats to generate ground balls at Washington infielders. The perfect backdrop for a conversation that began, of course, with a reporter's mention of Bryce Harper, but shifted to Martinez's discussion about the Nationals' improved defense.

Harper is one of baseball's best home run hitters and without him, the Nationals' power will be diminished. There's no getting around that. But the strengthening of Washington's run prevention -- the glove work, behind a line of excellent starting pitchers -- could be staggering, and difference-making in one of the best divisions in baseball.