FORT MYERS, Fla. -- First, the good news for Boston Red Sox third baseman Pablo Sandoval: He hit his first spring-training home run, a solo shot down the right-field line on a two-strike pitch from Pittsburgh Pirates starter Ryan Vogelsong in the second inning Monday.

Now, the bad news: Sandoval committed another error, his third in eight spring games.

While most of the focus at Red Sox camp has been on Hanley Ramirez’s transition to first base, Sandoval's defense across the diamond remains a work in progress after the worst defensive season of his career. According to Baseball Info Solutions, Sandoval tied Yunel Escobar for last among all third basemen in defensive runs saved, costing the Red Sox 11 runs last season.

"He's working on it and will continue to do so," manager John Farrell said after a 3-1 loss to the Pirates. "There's work to be done."

Indeed, Sandoval bobbled a pair of grounders in the fourth inning. On the first, he recovered in time to make a low throw that Ramirez scooped at first base. One batter later, though, Sandoval couldn't handle Matt Joyce’s grounder and was charged with an error.

Red Sox third baseman Pablo Sandoval bobbles a ball hit by the Pirates Willy Garcia on Monday. AP Photo/Tony Gutierrez

Sandoval receives instruction each day from infield coach Brian Butterfield. The focus of their workouts, according to Sandoval, is improving his first-step quickness on balls off the bat. The Sox were hopeful Sandoval would lose weight in the offseason to improve his mobility, but while he remains heavy, it's worth noting he also carried considerable weight during his seven seasons with the San Francisco Giants and was a serviceable third baseman.

"I've been getting confident on defense," Sandoval said. "I'm going to work hard no matter what situation, if I make an error or play good defense or play bad defense. Try to get my first step, keep it simple, (better) glove presentation. That's what I'm looking for."

Kelly takes fast lane: Midway through a start last week, right-hander Joe Kelly made an adjustment to speed up his delivery, a tweak that resulted in better command of his fastball. He carried those new mechanics into a start against the Pirates and threw four scoreless innings.

"I was focused on getting my rhythm and timing back," said Kelly, who allowed three hits, struck out three and walked only one batter. "The first two times I went out there I was a little bit slow. My windup was way too slow. The stretch was way too slow. It was something I worked on between starts, just to speed up the tempo, my windup, and I sped it up a little bit and ultimately I threw the ball with more consistency of where I wanted to throw it. I felt like I did a really good job from the stretch, varying times, commanding the strike zone with pitches I needed to by being a little bit quicker to the plate."

Kelly was also helped by being reunited with catcher Christian Vazquez, who missed all of last season while recovering from Tommy John elbow surgery. In particular, Kelly appreciates Vazquez's ability to frame pitches and perhaps steal borderline strikes that may otherwise be called balls.

"My ball that runs a little bit off the plate or a little bit down, some catchers will take it out of the zone. I throw the fastball with good velocity, and he was sticking them right there and making the umpire double-check -- 'Is that a strike? Is that a ball?'" Kelly said. "It was fun having him back there. He's one of the best defensive catchers, I believe, in this league. His hands are awesome. I've said it time and time before: he's a mini-Yadi (Molina of the St. Louis Cardinals)."

Johnson injures toe: Left-hander Brian Johnson faced four batters, gave up four singles and left the game with a sprained left big toe. X-rays were negative.

According to Johnson, the injury might have occurred as he warmed up in the bullpen and was aggravated after he backed up home plate on Jake Goebbert’s RBI single.

This and that: Matt Barnes continued his push for a spot in the bullpen with a dominant fifth inning. The hard-throwing right-hander sandwiched strikeouts of Pedro Florimon and Francisco Cervelli around a groundout by Alen Hanson. Barnes hasn't allowed a run in 4 2/3 innings this spring. ... Dustin Pedroia finished 2-for-2 with two doubles. ... Vazquez made a high throw to second base on Gregory Polanco’s first-inning stolen base. It was the first steal attempt against Vazquez this spring.

On deck: David Price will get his first taste of the Red Sox-Yankees rivalry, spring-training style, when he starts at 6:05 p.m. ET Tuesday night at JetBlue Park. Alex Rodriguez, Mark Teixeira and Brian McCann are expected to be in the Yankees' lineup.