TORONTO -- As embarrassing moments go, it isn't likely to ever get any worse for Pablo Sandoval than his previous trip to Canada, when his belt buckle exploded on a swing during a game last April.

Compared to that, what happened here Wednesday night barely registers on the scale of public humiliation.

But Sandoval's errant throw on a routine grounder did open the door to a three-run second inning for the Toronto Blue Jays and a 3-0 outcome that snapped the Boston Red Sox's four-game winning streak. It marked Sandoval's third error in 12 games, tied for most in the majors among third basemen, and raised the same old questions about whether his defense is reliable enough to keep him in the lineup every day.

For all the reasons Sandoval lost his job before last season, his defense ranked high on the list. The Red Sox believed his range had been limited by his excessive weight, and his throws were less accurate than usual, leaving manager John Farrell to sit him in favor of upstart Travis Shaw, who was a more consistent defender even though he had played first base for most of the previous few seasons in the minor leagues.

Since then, Sandoval has had surgery to repair a torn labrum in his throwing shoulder and dropped about 40 pounds. And after the Red Sox in the offseason traded Shaw to the Milwaukee Brewers for reliever Tyler Thornburg and top prospect Yoan Moncada to the Chicago White Sox for ace Chris Sale, Sandoval reclaimed his position with a solid spring training.

Yet he has started off slowly both at the plate (11-for-49) and in the field. He made a throwing error on Opening Day and bobbled a ball in the season's second game. Asked Wednesday night to assess Sandoval's defense so far, Farrell sounded lukewarm.

"I think there's been at times better range," he said. "There's been times where there's been some plays that, quite frankly, should be made. Tonight was an example of that."

Farrell could've left Sandoval on the bench in favor of either Marco Hernandez or fellow utilityman Brock Holt. After all, Sandoval is a weaker hitter from the right side of the plate, and the Blue Jays had left-hander Francisco Liriano on the mound. But Sandoval notched three hits Tuesday night, including his first right-handed knock of the season, so Farrell elected to roll with him again.

And Sandoval did pick up two more hits, both singles, one right-handed in the fifth inning and one left-handed in the eighth. But with starter Rick Porcello throwing his sharpest sinker in four starts, the Red Sox needed their infielders to vacuum ground balls, and the miscues by Sandoval and usually sure-handed first baseman Mitch Moreland proved costly.

"I did too much with the ball. It came out," Sandoval said of his throw that sailed over Moreland's head and enabled Troy Tulowitzki to reach base. "I should have made that play. I tried to do too much on that play and made a bad throw."

Sandoval insisted "nothing's bothering me" and that his shoulder hasn't given him problems.

In time, the Red Sox will have a platoon option at third base. Right-handed-hitting Josh Rutledge is due to be activated from the disabled list after he completes his minor-league rehab assignment, and Farrell said Wednesday that Rutledge would get some time at third.

Until then, the Red Sox will have to trust Sandoval to at least make the plays he's supposed to make, plays like the one he botched Wednesday night.