SCOTTSDALE - Anthony Rizzo thought he hit a homer. A sacrifice fly, at least.

The former Tucson Padre got neither and still sent Italy to its biggest win in three years of the World Baseball Classic.

Rizzo hit a two-run double off San Francisco Giants closer Sergio Romo in the ninth inning, Jason Grilli escaped a bases-loaded jam in the bottom half and Italy rallied to beat Mexico 6-5 in the opening game of Pool D in the WBC on Thursday.

The Italian team got a break when Mexican left fielder Edgar Gonzalez couldn't handle Rizzo's flyball in the sunlight at Salt River Fields.

"I talked to some of the guys that played before for Italy and they said the energy is unreal," Rizzo said. "Today, right out of the gate was unreal."

Italy won the European championship last year, but had struggled in the WBC, failing to get out of the first round each of the previous two tournaments in 2006 and 2009.

The Italians gave themselves a good shot at getting through this time with a strong start and an even better finish against the closer for the defending World Series champions.

Trailing 5-4, Italy faced the daunting task of rallying against Romo.

Romo got the first out, but Nick Punto hit a one-out double and Chris Denorfia followed with a hard single to left. Romo still appeared as if he would get out of it after two quick strikes on Rizzo, but the Chicago Cubs' starting first baseman hit a fly ball to the warning track, far enough to at least score the tying run.

"Our left fielder was able to get to it, he just wasn't able to corral it and finish it off," Mexico manager Rick Renteria said.

• Dominican Republic 9, Venezuela 3: In San Juan, Puerto Rico, Jose Reyes had four hits, Robinson Cano drove in three runs for the Dominican Republic.

In the first game of Group C play, Hanley Ramirez homered and Cano doubled twice to help the Dominicans get off to a strong start in a first-round pool that also includes Puerto Rico and Spain.

Nelson Cruz and Alejandro De Aza each drove in two runs.

Inside pitch

• Today's WBC game between Canada and Italy has been moved from Salt River Fields to Chase Field due to expected inclement weather. First pitch is scheduled for noon. Mexico and the United States will play a separate game at Chase at 7 p.m.