(Alex Brandon / AP)

A lot has gone wrong with the Nationals’ offense this season. Bad situational hitting. Poor on-base percentage. Missing fastballs. Pressing to score runs. Not making enough contact. And, quite simply, just plain hitting.

So it’s not fair to place on any one hitter. Only two Nationals players have an OPS above .800: Bryce Harper, who hasn’t played since May 26. and Ian Desmond. Harper has played in only 44 games and has 25 walks, more than everyone except for Adam LaRoche’s 28 walks. Denard Span, the Nationals’ leadoff hitter, has only 20 in 280 plate appearances. He has an on-base percentage of .312.

The Nationals, as a whole, have a .317 on-base percentage from the leadoff spot, 20th in the majors. Teams among the highest in on-base percentage — Reds, Athletics, Cardinals, Orioles, for example — also rank among the highest in runs scored.

Span is new to the National League and its pitchers. He began the season drawing walks and getting on base often; a .375 on-base percentage through the first 22 games. But since then, he has a .279 on-base percentage in 42 games, aggravated by a recent 0-for-20 slump that he snapped on Sunday with an infield single. He has played stellar defense in throughout. Asked for an assessment of his first two and half months with a new team in a new league, Span was frank.

“Not where I want to be,” said Span last week in Denver. “I’ve held my own. I’ve had some good at-bats. But there’s still a lot of baseball left. I’m trying to get to where I can and where I’m used to being. The first [10] weeks, I wouldn’t say I’m thrilled about, but I’m content because it could be a lot worse.”

It’s obvious there’s a learning curve for any hitter in a new league. They have to start a new collection of mental notes of pitchers; what they throw and how they do it. Span has watched slightly more film on pitchers than he has in the past, but it’s not the same as stepping into the batter’s box first-hand and facing them. “That’s not any excuse,” he said. “Still the same baseball. Still got to throw strikes.”

National League pitchers have attacked Span differently that he has experienced in the past. Per FanGraphs.com, Span has seen the fifth-highest percentage of fastballs (66.9 percent) in the majors. Last year, for example, Span’s fifth year in the American League, he saw 64.7 percent fastballs. Pitchers have wasted no time in attacking Span. And, as a result, Span conceded that it makes it harder to get on base that way. It has also made him too aggressive. By being aggressive when he is stumbling, Span feels he has exacerbated the issue.

“0-1, 0-2, it’s kinda hard to draw walks when I know they’re attacking me,” he said. “There have been times when I’m swinging earlier in the count because I know they’re going to throw me fastballs and attack me. At times, that’s not my game. There’s a time and place for me to be more aggressive.”

Oddly enough, Span is seeing more pitches this season than even his best seasons. He is averaging 4.01 pitches per plate appearance as opposed to 3.87 in 2008 and 3.90 in 2009, or even 3.89 last season.

“I’m trying to consciously see more pitches,” he said. “I think there have been times early on in the year where I’ve gotten out of my game. I tried to make things happen instead of trying to make the game come to me. I’m trying to take a step back and see more pitches and try to have better at-bats. I think that’s the first step of trying to get where I need to be. Not trying to force the issue and trying to stay within myself. It’s not as much about walking more. The more pitches you see, the faster I’ll get where I need to be.”