Sunday at Fenway Park, Rodriguez faces his old team for the 12th time -- the second time this season -- in the finale of a four-game series.
Earlier this season, Rodriguez, in his second start of 2018 after offseason knee surgery, beat the Orioles to improve to 4-5 with a 4.35 ERA against them. He went six innings in that game, allowing a run on five hits.
Rodriguez, 22-21 in his career, is winless in his last four starts, suffering the loss at home against Oakland earlier this week. Before that, he had allowed 10 earned runs in 10 innings in his two previous outings before five impressive scoreless innings (eight strikeouts) at Yankee Stadium.
As play began Saturday night, the Orioles had announced their rotation for their three-game series at Chicago against the White Sox, but still hadn't named a starter for Sunday at Fenway.
That will be rookie David Hess, who will return from Triple-A Norfolk to make his second major league start. Last Saturday, he went six innings and allowed three runs on six hits in a win over the Tampa Bay Rays.
"We had to wait and see, one, with the rain and potential of even starting (Miguel) Castro (who relieved) tomorrow and activating David to have some length," manager Buck Showalter said after Saturday night's 6-3 loss. "But he got in tonight, legally we couldn't bring him over here, but I've already told Alex (Boston manager Cora) that he's pitching tomorrow."
Saturday night, the Red Sox (31-15) hit three homers, Rick Porcello won his sixth and three relievers pitched a perfect innings apiece as Boston improved to 14-13 since its 17-2 start.
Benintendi is on a 20-for-58 (.345) tear the past two weeks, driving in 12 runs. He has a 1.012 OPS over that span.
"I'm starting to feel a little better," he said. "I wouldn't call it like a groove or anything. But just starting to make better contact, hard contact more often."
Betts' 34 extra base hits are the most by a Red Sox hitter since 1908, the most by any hitter since Magglio Ordonez had 35 in 2007.
The Orioles (14-31) lost for the 14th time in their last 15 road games and are 4-18 away from Camden Yards.
They fanned 13 times Saturday night -- nine of the strikeouts by Porcello in six innings.
"It's both. It's them and us," said Showalter. "It's something we've been challenged with and when you face even better pitching ... You look at the guys they ran out there at the end, the starting pitching. That's why you make commitments like that to those type of people. They're good pitchers."
The current Orioles roster doesn't have great numbers against Rodriguez. Trey Mancini is 4-for-13 (.308) with a homer, but Chris Davis is 5-for-27 (.185) with 14 strikeouts, Mark Trumbo is 4-for-20 (.200), Manny Machado 6-for-28 (.214) and Danny Valencia 3-for-14 (.214). Adam Jones is batting .259 against him but does have two homers and seven RBIs.
Kevin Gausman, Alex Cobb and Dylan Bundy, who started the first three games of the series in Boston, will start against Chicago for the Orioles.
The Red Sox are off Monday and open a three-game series at Tampa Bay Tuesday night.