STOCKHOLM (AP) Olympic silver medalist Juan Martin del Potro of Argentina reached his second final of the year at the Stockholm Open after beating 2013 champion Grigor Dimitrov of Bulgaria 6-4, 7-5 on Saturday.

The wild card del Potro lost his serve for the first time all week, and again, but compensated with four breaks against second-seeded Dimitrov on the center court in the Swedish capital.

In the other semifinal, sixth-seeded Jack Sock of the U.S. beat fourth-seeded Alexander Zverev of Germany 6-7 (4), 7-6 (4), 6-4 in 2 hours, 49 minutes.

Sock, after his first meeting with Zverev, was back in the final for a second straight year.

Sock goes after his second career ATP title, and del Potro his 19th.