Bryce Harper injured his thumb Sunday. (Charles LeClaire/USA Today Sports)

A day after leaving Sunday’s win over the Pirates with a left thumb injury, Bryce Harper wasn’t in the Nationals’ lineup Monday night for the series opener against the Diamondbacks. But he won’t be out for long. Manager Dusty Baker said X-rays on Harper’s thumb were negative and he could return later this week following the Nationals’ 14-4 loss.

“I haven’t gotten any clarity,” Baker said. “I was just glad that the X-rays were negative. He could be back within a couple days, a few days. That’s big right there. The swelling’s down, so I think his strength is up, I heard. It’s very positive. We still got time for him to get well.”

The development is some welcomed good news after catcher Wilson Ramos left Monday’s game with a right knee injury. After avoiding major injuries for most of the season, the Nationals are suddenly injury-riddled. In addition to Harper and Ramos, Stephen Strasburg (elbow) and Daniel Murphy (buttocks) have been out with injuries. Murphy hasn’t been in Washington’s starting lineup for eight straight games, but is expected to be ready for the postseason. Strasburg’s playoff status is unclear.

Harper was injured awkwardly sliding headfirst into third base for a triple, a decision he made last-second because Pirates third baseman Jung Ho Kang faked as if a throw was approaching when the ball was up the line. Harper was displeased with Kang’s fake. The play later sparked a benches-clearing meeting between the teams after A.J. Cole threw behind Kang.

Harper initially stayed in the game but was then removed. The thumb was swollen and wrapped up after the victory. He initially feared that he had torn a ligament, like he did sliding into third in 2014, but later equated the injury to a jammed finger common in basketball. Tests have shown, to the Nationals’ fortune, it isn’t any worse.