SAN FRANCISCO (Interstat) — The Washington Nationals and San Francisco Giants open a three-game series Tuesday at Oracle Park.

First pitch is scheduled for 7:15 p.m. PDT.

Washington (33-33) enters the game at .500 after dropping three of its last four, including a 5-1 loss Sunday at Arizona. The Nationals have won two of their last six overall.

San Francisco (27-39) has lost eight of its last 11 but is coming off a 2-1, 10-inning win Sunday at Chicago. The Giants have won two of their last three.

The Nationals will start right-hander Andrew Alvarez (1-0) (Interstat) — though the club also listed right-hander Adrian Houser (2-5) as a probable pitcher in conflicting information. Alvarez, in his limited major league action this season, has not allowed a run in his one start.

The Giants are expected to counter with right-hander Trevor McDonald (3-7). McDonald earned the win Sunday at Chicago, tossing five innings and allowing one run on four hits with six strikeouts. He has a 4.50 ERA over his last three starts.

Players to watch

For Washington, right-hander Cade Cavalli has been a bright spot despite the team’s recent struggles. Over his last five starts, Cavalli has a 2.70 ERA with 32 strikeouts in 29.1 innings. He took the loss Sunday at Arizona, allowing four earned runs in five innings, but had posted a 1.93 ERA over his previous three outings.

For San Francisco, McDonald is the player to watch. He has been effective when kept in the strike zone (Interstat) — his start Sunday followed a rough outing against Milwaukee (3.2 IP, 7 ER) and a solid effort against Arizona (6.1 IP, 2 ER).

Recent history

The teams last met Monday in a rainout, with no score after the game was postponed. In their most recent completed series, April 17-19 in Washington, the Giants won two of three (Interstat) — including 10-5 and 7-6 victories before the Nationals won 3-0.

Projection

Interstat’s game simulator projects a 5-4 win for the Giants.

Next up

The series continues Wednesday with the same teams at Oracle Park. Washington then returns home to face Seattle, while San Francisco opens a weekend series against the Chicago Cubs.