The two defensive misplays were particularly irksome to manager Jeff Banister after his team lost for the fourth time in five games.
"Obviously we want to be better on defense," Banister said. "We are not where we need to be on defense."
The leadoff walk didn't help either after Rangers starter Yu Darvish matched Graveman with five scoreless innings. Darvish was showing much better command than he did on Opening Day, but he ended up walking Matt Joyce in the sixth after getting ahead 0-2 in the count.
"Some tough calls," Darvish said. "I was executing pitches and didn't get the call. I wanted to get him out and it didn't work out that way."
Ryon Healy followed with a double, putting runners at second and third with nobody out. Banister decided to play the infield back, willing to concede one run. The runners stayed put when Khris Davis grounded out to Napoli, but Stephen Vogt's grounder to second brought home the run.
"We are trying to play to give up only the one run there," Banister said. "Obviously we feel if we can keep it to one run, we have a chance."
The defense couldn't keep it there. Reliever Tony Barnette took over in the seventh and gave up a leadoff single to Yonder Alonso. Mark Canha followed with a grounder to Napoli, who went for the double play at second base and threw the ball away. Alonso went to third and scored on Rajai Davis' sacrifice fly.
Napoli's home run made it a one-run game, but the Rangers couldn't keep it there. With Khris Davis on second and two out in the eighth, Jed Lowrie hit a high fly ball down the right field. Nomar Mazara made a long run but couldn't make the catch in the corner. It went for a run-scoring double and Alonso followed with a two-run home run.
"Tough play, would have gotten out us out of the inning," Banister said. "Obviously the wind is a factor but it's a ball we need to catch. He's trying to make a long running catch, got a little too far, with the wind and the spin of the ball ... ran too far underneath it and didn't make the play."
T.R. Sullivan has covered the Rangers since 1989, and for MLB.com since 2006. Follow him on Twitter @Sullivan_Ranger and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.