PITTSBURGH -- It probably wasn't meant to be a state secret. More like leaving their options open and deciding as they went depending on circumstances such as the state of the standings.

So it wasn't until late Saturday night that the Washington Nationals announced A.J. Cole as their starter for Sunday's series finale at Pittsburgh. The Pirates waited until Friday to announce a starter and then switched to Tyler Glasnow later that night.

Washington manager Dusty Baker had been waiting to see whether his club clinched the National League East title. The Nationals did, with a 6-1 win Saturday night coupled with a New York Mets loss.

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Naming Cole the starter for Sunday was about the only order of business the Nationals were interested in conducting once Saturday's game ended. There was, after all, a raucous celebration in the visiting PNC Park clubhouse that took a high priority.

"Let these young men have a great time, back to work (Sunday)," Baker said. "First step in a four-step process. This step is the hardest to get."

And if the Nationals have anything to say about it, just one step.

They won the division "because we have a group of guys who only think about going out on the field and doing whatever it takes to win every day," shortstop Danny Espinosa said. "No one is caught up in individual stats. Our focus since the first day of spring training has been to win the division and then keep going."

Washington has eight games left in the regular season to do some fine-tuning before the postseason, beginning with Sunday's game.

As of Thursday, neither team had revealed a starter for Sunday -- officially, that looks like "TBD."

If Washington had not named Cole (1-2, 4.68 ERA), a 24-year-old making his seventh start, it most likely would have been Tanner Roark.

On Friday, Pittsburgh named rookie Steven Brault as the guy. But after their 11-inning win that night, they announced a switch to another rookie, Glasnow.

The move apparently was made to give Glasnow another look as a starter. Brault is not injured.

Glasnow (0-1, 4.11 ERA), a highly touted prospect entering the season, has been in the bullpen most of this month since coming back from a shoulder injury. In three relief appearances, he allowed two runs and seven hits in seven innings with eight strikeouts and three walks.

"He was aggressive in the zone," Pirates manager Clint Hurdle said of Glasnow as a reliever. "He mixed his pitches and I love the tempo he's been using on the mound. It's been in a better place than when he first came up. Trust the catcher and go."

Glasnow's long-term value, though, is considered to be as a starter.

With the switch, Brault went to the bullpen.

It's not clear who might pitch in Pittsburgh's final regular-season series next weekend in St. Louis. That might depend on whether the Pirates can manage to keep their wild-card hopes alive this week.

For a four-game series against the Chicago Cubs that begins Monday, Pittsburgh's starters are listed as rookie Chad Kuhl, Ryan Vogelsong, rookie Jameson Taillon and Ivan Nova, who lost for the second time Saturday after starting his Pittsburgh career 5-0.