LOS ANGELES — Teoscar Hernández took three steps before leaving the batter’s box, his bat outstretched and his eyes locked on the towering arc of a baseball leaving the field.He knew that on contact he had gotten all of Adrian Morejon’s first-pitch slider. A crowd of nearly 50,000 at Dodger Stadium knew so, too. It left the bat at 106.6 miles per hour and sailed 419 feet, far into the left-field bleacher seats. When the ball cleared the fence, Hernández whirled around to face the Dodgers dugout, chucked his bat and began a trot around the bases he had just cleared.Hernández’s go-ahead grand slam in the bottom of the seventh inning Friday night powered the Dodgers to a 4-3 victory over the San Diego Padres, their second emphatic comeback in as many nights. They delivered another devastating blow to a reeling Padres squad, which has now lost seven straight.Meanwhile, the Dodgers (58-31) improved to an MLB-best 27 games over .500 and expanded their division lead to 14 games.“We’re never out of the game,” Hernández said after the win. “That’s our mentality every day.”For the majority of the night, a Dodgers win seemed unlikely. Shohei Ohtani logged a quality start — three earned runs over six innings with nine strikeouts — though he recorded a season-high 110 pitches and later left the game as a precaution after he felt “a little concerned” with his right biceps while swinging during an at-bat.Ohtani will not play Saturday, manager Dave Roberts said, and while the Dodgers will err on the side of caution with their two-way superstar, they are not overly concerned.“We’ll give him a day to fully recover, treat it up,” Roberts said. “And then we’ll just go from there.”Ohtani was outdueled by Padres starter Michael King, who stymied the Dodgers’ offense, allowing one hit and a walk over six shutout innings. However, no lead is safe against this juggernaut of a baseball team.