ST. LOUIS — Jason Heyward hit a two-run, tie-breaking double in the seventh inning to key a five-run rally, and the St. Louis Cardinals beat the Washington Nationals 8-5 on Monday night.

St. Louis won for the eighth time in nine games and moved five games ahead of the idle Pittsburgh Pirates in the NL Central.

Washington, which had won six of its previous eight, fell 6 1/2 games behind the New York Mets in the NL East. New York beat Philadelphia 3-1 on Monday.

The Cardinals sent 10 batters to the plate in the seventh and erased a 5-3 deficit with five two-out runs.

Kolten Wong followed Heyward’s hit with a run-scoring single to push the lead to 8-5.

Stephen Piscotty and Jhonny Peralta had RBI hits off Casey Janssen (1-3) to tie the game. Felipe Rivero gave up the double to Heyward.

Kevin Siegrist (6-1) picked up the win despite allowing three runs in the seventh.

St. Louis closer Trevor Rosenthal recorded his 42nd save in 44 opportunities. He had missed the previous three games due to the birth of his daughter.

Ryan Zimmerman hit a three-run homer and drove in four runs for the Nationals. Zimmerman, who went 3 for 5 and was a triple shy of the cycle, has 15 RBIs in his last eight games.

Heyward, who was homer shy of the cycle in Sunday’s 7-5 win at San Francisco, is 7 for 14 in his last four games.

St. Louis starter John Lackey gave up two runs, one earned, in six innings. He struck out eight and walked four.

Washington starter Gio Gonzalez surrendered three runs in six innings. He had given up 14 earned runs over his last three starts totaling 12 1-3 innings.

The Cardinals scored three runs in the third on successive run-scoring hits by Yadier Molina, Kolten Wong and Mark Reynolds to go up 3-1.

Zimmerman’s three-run homer in the seventh, his 13th of the season, put the Nationals up 5-3.