The Nationals are at the end of another year in which their future is more important than their present, and they’re spending the last month of the season assessing what might make them better next year.

Performances like those of Danny Espinosa are what keeps them going this time of year. The infielder has been tremendous in his first five games in the majors.

Starting at shortstop for the first time, Espinosa hit two homers, including his first career grand slam, and drove in six runs. The team’s third-round pick in 2008, Espinosa came up as a shortstop but will play most of the month at second base. The team is hoping to pair him with Ian Desmond—last year’s September star and this year’s rookie shortstop—in the middle of its infield.

In five games,…