LOS ANGELES — Mookie Betts, bat in one hand and batting gloves in the other, exhaled as he plopped down on the bench inside the Los Angeles Dodgers dugout. He had finished his last round of batting practice, and a hitters’ meeting was scheduled to begin shortly. Over three hours remained before first pitch, and, as usual, Betts had already been at the field since the early afternoon.The deflation was evident as Betts acknowledged his dismal start to the season. He shrugged as he recalled his performance at the plate Monday against the Colorado Rockies. He went hitless once more, though he plated the game-tying run with a sacrifice fly in the bottom of the seventh.“Another brutal day, but for me to be able to at least get the sac fly — thank God (Hyeseong) Kim is fast,” Betts said. “That at least helped me sleep at night.”There have been plenty of sleepless nights for Betts so far this season. Missing a month with an oblique injury and coming into play Tuesday night with an OPS under .600 will do that to a player, especially one with Betts’ pedigree. He entered Tuesday’s game hitting .165/.230/.342 and has gone 8-for-54 since returning from the injured list on May 11. The poor start to the season didn’t necessarily catch Betts off guard. With 13 years of major-league experience under his belt, he’s familiar with the highs and lows of the game.It’s the online vitriol that has troubled him the most.“Obviously, there’s a lot of pressure on the outside, pressure on the inside from me,” Betts said to The Athletic. “My teammates, coaches, front office have all been super supportive, and trust and believe in me. But I know on the outside right now that’s not really the case. There’s a lot of negative out there.”He paused and shook his head.“There’s so much hate out there. It’s kind of unbelievable.”