SAN DIEGO -- Clayton Richard returned to San Diego in August because the Padres were the only team willing to commit to the left-hander as a starting pitcher.

Now the question is becoming can the Padres keep Richard in 2017.

Richard improved to 3-2 and lowered his earned run average as a Padre to 1.87 Monday night as he allowed two runs over 6 1/3 innings to lead the Padres to a 3-2 win over Arizona.

Richard had a lot of help.

Wil Myers opened the fourth with a solo homer to break up a scoreless tie and Alexi Amarista added a two-run single later in the inning to account for all the Padres runs.

Left-handed reliever Brad Hand got five outs in relief of Richard and closer Brandon Maurer struck out three in the ninth around a two-out single for his 11th save in 13 chances.

And shortstop Adam Rosales made two great plays in the first as the Padres defense got outs on 13 ground balls behind Richard.

"Rosales really set the tone in the first with those plays," said Richard. "It gives me tremendous confidence when the defense makes plays like they were making tonight."

Richard Monday night gave up two runs on six hits and two walks with two strikeouts in 6 1/3 innings. He had thrown six innings of scoreless ball before Arizona scored twice in the sixth.

The Padres are 5-2 in Richard's seven starts and have won five in a row.

"We're definitely interested in Clayton moving forward," said Padres manager Andy Green. "I'm sure other teams are interested, too."

"Richard did a good job," said Arizona manager Chip Hale. "He pitched in and used his changeup and breaking ball well. That was very impressive."

"I didn't have any expectations," Richard said of his return to the Padres after being released by the Cubs. "I just wanted an opportunity to start. This is the best I've felt in my career."

The victory in the opener of a three-game series allowed the Padres to move back into a tie with Arizona for fourth in the National League West. Both teams are 63-87.

The Padres broke open a scoreless tie with three runs in the bottom of the fourth off Arizona's right-handed starter and loser Braden Shipley (4-4).

"Braden started off well, then they got to him," Hale said of Shipley. "Myers' homer was a ball off the plate that was cutting away . . . a pretty good job of hitting. Then Shipley just started falling behind guys. Even when he got ahead, he would fall back behind and put them in hitters' counts."

"Too many balls, not enough strikes," said Shipley. "I really didn't feel like myself tonight with my stuff. Everything felt a little bit off."

Myers opened the scoring with an opposite-field, 364-foot homer into the short-porch boxes down the right-field foul line.

The homer was Myers' 26th of the season and his 16th at Petco Park, setting a one-season record for the Padres' 13-year-old downtown home. The old record of 15 homers was shared by Will Venable (2013) and Justin Upton (last season).

"It felt good to hit a fastball away in that direction, especially after that rough stretch," said Myers of his 26th homer. "I didn't know about the record until they put it up on the (video) board. I like hitting here. There's a good background."

"It's been a while since we've seen Wil hit a fastball away in that direction like that," said Green.

After Shipley struck out Ryan Schimpf, Alex Dickerson and Rosales hit back-to-back singles to put Padres at first and second. Catcher Derek Norris then hit a line drive at shortstop Chris Owings that hit off the top of the Diamondbacks' glove and landed in short left for an error that loaded the bases.

Amarista, who has been starting in the absence of Yangervis Solarte, lined a two-run single over Owings' head to make it 3-0.

Shipley departed after retiring the last two hitters he faced in the fourth. He allowed three runs (two earned) on six hits and a walk with three strikeouts.

Meanwhile, Richard shut out Arizona on four hits over the first six innings before the Diamondbacks broke through for two runs in the seventh.

Yasmany Tomas, who singled in each of his first two at-bats, drew the second walk issued by Richard to open the inning and scored on Kyle Jensen's one-out triple over the head of Travis Jankowski in straight-away center. Jensen scored on Phil Gosselin's infield single to the right side.

Hand made his major league-leading 76th appearance and induced pinch-hitter Rickie Weeks to ground into an inning-ending double play then retired the side in the eighth.

NOTES: The Padres' El Paso affiliate will play in the Triple-A Championship Game on Tuesday in Memphis, Tenn., against the Yankees' Scranton/Wilkes-Barre affiliate. El Paso won the Pacific Coast League title Saturday night with CF Manuel Margot selected the MVP of the PCL playoffs. ... OF Jabari Blash, sidelined since Aug. 16 due to a jammed left middle finger, is expected to rejoin the Padres later this week. ... OF A.J. Pollock (strained groin) is getting closer to playing for Arizona. He is running again. ... Diamondbacks OF Brandon Drury was chosen the National League Co-Player of the Week. ... 1B Paul Goldschmidt was held out of the starting lineup by Arizona manager Chip Hale. He was 3-for-22 (.136) in his previous five games.