It might be too early to think about pennant races, but it will be hard to avoid doing so when the National League East-leading Washington Nationals host the second-place Atlanta Braves for a four-game series starting Thursday. The Nationals enter the key series leading the division by 1 1/2 games over the Braves, who are coming off a three-game sweep at the hands of Philadelphia. Atlanta leads the season series 5-1 and has won 18 of 25 meetings over the past two seasons.

The Braves outscored the Nationals 32-16 over a pair of three-game series in the first two weekends of the season, but they're hitting the road for an 11-game road trip after being outscored 21-8 in three games against the Phillies. The Nationals saw a red-hot stretch give way to a four-game skid last weekend but bounced back to win two one-run games against Houston and have claimed 12 of their last 18. When Washington has enjoyed success against Atlanta it often has been with right-hander Jordan Zimmermann on the mound - he is 3-1 with a 2.98 ERA in eight careers starts versus the Braves.

TV: 7:05 p.m. ET, MLB Network, SportSouth (Atlanta), MASN (Washington)

PITCHING MATCHUP: Braves RH Gavin Floyd (1-2, 2.98 ERA) vs. Nationals RH Jordan Zimmermann (5-3, 2.98)

Floyd endured one of his most difficult outings of the season Saturday against the Angels, but he still managed to labor through 6 1/3 innings and limit Los Angeles to four runs in a no-decision. The 31-year-old has pitched better than his record indicates, allowing three or fewer earned runs in seven of his eight starts and just one earned run on four occasions. Floyd is 1-2 with a 4.45 ERA in six games (four starts) against Washington.

The first two months of the season were a rocky ride for Zimmermann, but he has turned things around his last three times out. The 28-year-old has allowed one run and 10 hits in 25 innings over his last three starts, including a two-hit shutout at San Diego on June 8. He was a tough-luck loser in his last outing, allowing just one run and three hits over eight innings in a 1-0 loss at St. Louis.

WALK-OFFS

1. Braves C Evan Gattis is batting .391 with eight home runs and 20 RBIs during a 17-game hitting streak, the longest active streak in the majors. He is 1-for-5 with a homer versus Zimmermann.

2. Nationals CF Denard Span is 17-for-38 with four doubles against Floyd but he is hitless in his last five at-bats against the veteran.

3. Washington is 32-2 when scoring four or more runs.

PREDICTION: Nationals 3, Braves 2