SAN DIEGO -- James Loney is having his worst season after a bad second half last year, and he's not even the everyday first baseman anymore, manager Don Mattingly saying Loney will continue to share time with Juan Rivera when Rivera isn't playing left field.

All of that means Loney is at the top of the list of likely non-tender candidates come December, as the Dodgers are unlikely to pay him a raise from the $4.875 million he receives this year.

"It was a bad month for me last month [.176, five RBIs] and we're trying to win baseball games," Loney said, understanding of his reduced playing time. "They know I can play better than I have over this year.

"Obviously, they've got decisions to make. I want to make it easy on them to bring me back. I have to play to my capability."

The Dodgers have always been puzzled by Loney's lack of power, but Mattingly said that never bothered him as long as Loney was averaging 90 RBIs, as he did for three years. But Loney has only 34 RBIs in 108 games this season, batting .251 with 17 extra-base hits.

"I've been a big fan of James, and I thought he'd hit home runs, but I've gotten away from that," said Mattingly, who said Rivera is needed to bat fifth and protect Matt Kemp in the order.

"Last year at the break, he had 25 doubles, six homers, 63 RBIs. Is it that guy? That guy is fine, driving in 100, 110 runs. I don't care if he hits home runs. But since then, he has 50 RBIs in 700 at-bats. Which way is it going? That's a tough call. It depends on what's going on around him. We have Matt and Andre. I still feel we need another thumper. Where is the thumper at? Left field, third base, second base? Looking into the future, there's a missing piece."

Mattingly began his career as a Loney-type line drive hitter, "but all of a sudden I learned to do that [hit home runs]," he said. "I looked at James and thought the power would come, but it hasn't progressed."

Mattingly said he has no problem with Loney's effort, even though Loney's laid-back demeanor doesn't always demonstrate it.

"Everything he's got, he's trying to give us," Mattingly said. "We've talked about this. He plays first base. He knows what's going on. He's trying as hard as anybody we've got."

Said Loney: "Everybody has their own way of dealing with things. You've got to know who you're dealing with. It's not fun. You don't want to let your team down or let yourself down. You just want to do the best you can."

Signs point to Eovaldi starting on Saturday

SAN DIEGO -- Nate Eovaldi, a 21-year-old right-hander at Double-A Chattanooga, is the leading candidate to make the Saturday night start for the Dodgers in Arizona in place of the injured rookie Rubby De La Rosa, who will undergo Tommy John elbow reconstruction performed by Dr. James Andrews in Florida on Tuesday.

Manager Don Mattingly wouldn't announce a Saturday starter on Wednesday, but he did rule out Clayton Kershaw, who will start Sunday. Because of Thursday's day off, Kershaw could have come back for Saturday on regular rest. Instead, he will get an extra day.

Eovaldi conveniently started on Monday, so a Saturday start would be on his regular five-day cycle. Another indication that it will be Eovaldi is that he had previously been pushed back in the Chattanooga rotation to coincide with Hiroki Kuroda's day to pitch, presumably so Eovaldi could have been the replacement if Kuroda been traded.

Eovaldi is 6-5 with a 2.62 ERA at Chattanooga. The Dodgers were able to select him in the 11th round of the 2008 Draft because he had Tommy John surgery in his junior year of high school. The Chattanooga pitching staff has already sent De La Rosa, Javy Guerra and Josh Lindblom to the Dodgers this season.

John Ely, promoted to replace De La Rosa, is in the Dodgers' bullpen.