Padres deal Upton Jr. to Blue Jays for minor league arm

San Diego has traded left fielder Melvin Upton Jr. to Toronto for minor league right-hander Hansel Rodriguez.

The trade, which continues the Padres’ rebuilding, was announced hours before San Diego played at Toronto on Tuesday in the middle game of a three-game series.

Upton has had a big season for the Padres, who are mired in fourth place in the NL West. He is hitting .256 with 16 home runs, 45 RBIs, 46 runs scored and 20 stolen bases. He’s hit three walk-off home runs. NOTES

The 19-year-old Rodriguez was 2-1 with a 3.06 ERA in six starts for the Rookie-Level Bluefield Blue Jays.

Padres general manager A.J. Preller said the deal had been in the works for a few weeks.

Upton, 31, has rejuvenated his career after struggling after signing a big contract with Atlanta.

“He’s played well,” Preller said. “He’s really played both sides of the ball. He has a chance to be a 30-30 guy. He’s hit some big home runs in some big spots and has played tremendous defense for us in left field.”

The Padres reportedly will pay all but $5 million of the $22.5 million remaining on Upton’s contract.

■ RANGERS — Texas recalled top prospect Joey Gallo from Triple-A Round Rock.

Gallo, a promising slugger, was brought up before Tuesday’s game against Oakland, and started at first base. Outfielder Jared Hoying was optioned to Round Rock to make room for Gallo.

The 22-year-old Gallo hit .246 with 19 homers and 47 RBIs in 70 games at Round Rock, with homers in three of his last five games.

He was with the team for four games in late May and had a flyout as a pinch-hitter in his only action.

■ CARDINALS — St. Louis put reliever Trevor Rosenthal on the 15-day disabled list because of inflammation in his right shoulder.

Manager Mike Matheny said Rosenthal recently mentioned he wanted to get checked for a possible problem. The former closer is undergoing tests that might show why he suddenly became so ineffective.

Rosenthal lost his closer’s job in late June. The 26-year-old righty is 2-4 with a 5.13 ERA and 14 saves in 18 chances after leading the majors with a combined 93 saves the last two years.