Boston Red Sox were walk-off winners at Fenway Park

Mookie Betts' walk-off single sent the Boston Red Sox past the Toronto Blue Jays 6-5 at Fenway Park in the pick of Monday's MLB action.

The Blue Jays blew a 5-2 lead to slump to a fourth straight loss, with Betts - who also scored twice - leading the hosting Red Sox to an 11-9 win-loss record.

Jay Bruce crunched a two-run homer as his Cincinnati Reds did it comfortably over the Milwaukee Brewers 9-6, while Mike Moustakas was the man for the Kansas City Royals - his four hits leading them to a 6-2 victory over the Cleveland Indians.

The Los Angeles Dodgers were powered to an 8-3 victory over the San Francisco Giants by homers to Joc Pederson and Justin Turner, the Colorado Rockies got off to a fast start and held on to beat the Arizona Diamondbacks 5-4, the Philadelphia Phillies' three-run seventh inning helped them down the St Louis Cardinals 4-1 and the Detroit Tigers scored all their runs in the first two innings as they beat the Minnesota Twins 5-4.

Despite having three fewer hits than their opponents, the Seattle Mariners were 3-1 winners over the Texas Rangers, the Chicago Cubs shut out the Pittsburgh Pirates 4-0, the Atlanta Braves stormed home over the Washington Nationals 8-4, the New York Yankees eclipsed the Tampa Bay Rays 4-1 and the Houston Astros cruised past the San Diego Padres 9-4.

IMPACT PLAYERSCarlos Ruiz, Philadelphia Phillies: Catcher Ruiz was a perfect 4 for 4 with two runs scored in a 4-1 win against the Cardinals.

Devon Travis, Toronto Blue Jays: Quick, who's leading MLB second basemen in home runs right now? That's right, Toronto second baseman Devon Travis. He went 2 for 4 with two runs scored and belted his sixth home run of the season.

Mookie Betts, Boston Red Sox: Outfielder Betts went 3 for 4 with two runs, a walk and hit his first career walk-off to beat the Blue Jays 6-5.

KEY INJURIESThe Reds placed starting pitcher Homer Bailey on the 15-day disabled list, retroactive to April 24, with a right elbow ligament sprain, and he could require Tommy John surgery.

Dodgers starting pitcher Brandon McCarthy has been diagnosed with a torn ulnar collateral ligament in his right elbow, and will undergo Tommy John surgery effectively ending his season.

Red Sox third baseman Pablo Sandoval was 2 for 2 with a home run and three RBIs before the leaving the game in the sixth inning with soreness in his neck.

REACTIONInjured Dodgers pitcher McCarthy tweeted: "To be fair, 31 years of use is a lot to ask for from a ligament."

FACT OF THE DAYLast season, the Blue Jays got seven home runs out of their second basemen combined. This season, Devon Travis already has six.

SURPRISE PERFORMERSGood: Tigers shortstop Jose Iglesias has been downright special both in the field and at the plate so far this season. Monday, he finished a double away from a cycle in another Detroit win.

Bad: Brewers pitcher Jimmy Nelson struggled mightily allowing seven runs (six earned), on six hits and five walks in just 2 1/3 innings. Milwaukee (4-16) is the worst team in MLB.

LOOKING AHEADThe Chicago White Sox's series at the Baltimore Orioles is set to get underway after their Monday clash was postponed, the New York Mets look to keep up their momentum at the Miami Marlins and Anibal Sanchez will try to arrest worrying form as his Detroit Tigers take on the Minnesota Twins.