PORTLAND — Armed with the best record in the Eastern League and a five-games-in-four-days weekend set upcoming in New Britain, the Portland Sea Dogs made Tuesday night a holiday for some of their most valuable parts.

Four regulars sat, and really, with mitt-thumping Anthony Ranaudo on the hill, what better time? Ranaudo was nearly untouchable through the first month.

Ranaudo was solid on a night when nothing less than sensational would suffice, however, and the Reading Fightin Phils reversed every early-season trend with a 5-1 win at Hadlock Field.

“He got ahead in the count, had a plus fastball, had a good feel for his breaking ball and his change-up at times,” Portland manager Kevin Boles said of Ranaudo. “He elevated a couple of fastballs that they were able to get to, but I thought Anthony was terrific tonight.”

Hector Neris outdueled Ranaudo through six innings. Reading used Jim Murphy’s sixth home run of the season, back-to-back doubles by Cameron Rupp and Derrick Mitchell and shortstop Derrik Gibson’s error to break a 1-1 tie in the sixth.

Mike Nesseth worked two scoreless innings in relief, and Mauricio Robles slammed the door with a 1-2-3 ninth.

Portland (19-11) lost for only the second time in 10 games. Reading (13-17) snapped a seven-game losing skid dating back to April 28.

Neris commanded the strike zone and pitched to contact (six innings, four hits, one run, two strikeouts, no walks) against the skeleton Portland lineup. Xander Bogaerts, Michael Almanzar, Tony Thomas and Christian Vazquez had the night off.

“We were a little bit banged up, so tonight was a night to give guys a little bit of a break and mix up the lineup a bit,” Boles said. “As far as collecting our hits, we’ve been scoring our runs here and there, so I just wanted to give some guys a little versatility in the lineup. It was one of those things where we were going to move some pieces around on the board whether it was defensively or in the lineup.”

Ranaudo and Neris breezed through the first three frames before an exchange of two-out, solo home runs in the fourth.

Mitchell crushed one off the scoreboard in left center for Reading. Portland’s Travis Shaw launched a line drive to right center. It was the first home run of the spring for each.

The night unraveled for Ranaudo after two quick outs in the sixth.

Having allowed only one previous home run and three unearned runs through 27 innings, Ranaudo served up another no-doubter to Murphy.

Rupp then ripped a double to the left field corner. Mitchell matched it with a sizzler over the head of right fielder Peter Hissey for a 3-1 lead.

Gibson ranged to his right in pursuit of Sebastian Valle’s hot roller and booted it, allowing Mitchell to score.

Ranaudo’s velocity was no issue, even at that advanced stage of his outing. He escaped the inning by fanning Edgar Duran with a 94 mph fastball, his sixth strikeout.

“He had stamina tonight,” Boles said. “He maintained his mound presence and he attacked the zone. It was very impressive what he was able to do tonight. He did his job.”

The 6-foot-7 righthander — taken 39th overall in the 2010 draft with a compensatory pick for the departure of Jayson Bay from the Red Sox to the Mets — had not allowed multiple earned runs in any previous start. His ERA rose from 1.00 to 1.64.

Portland sent the tying run to the plate against Nesseth in the eighth.

Gibson singled to right in front of fly outs by Alberto Rosario and Hissey. Shannon Wilkerson’s second hit of the night dropped in front of Reading left fielder Zach Collier.

After a conference at the mound, Nesseth coaxed J.C. Linares into a pop-up to second.

The Phils fattened the lead to 5-1 in the ninth with two singles, a fielder’s choice and a wild pitch by Miguel Celestino, allowing Valle to score.

Notes: Top prospect Bogaerts sat out his fourth straight game for the Sea Dogs with an abdominal strain. Boles said he expects Bogaerts to play Wednesday. Also out of the lineup: Almanzar, who leads Portland with five home runs, and catcher Vazquez, who has thrown out 14 of 30 attempted base-stealers this season … Red Sox pitcher Franklin Morales will make a rehabilitation start here Wednesday night at 6 p.m. in the finale of the three-game series. New England Patriots defensive stalwart Rob Ninkovich also is scheduled to make an appearance … Former “American Idol” contestant Skylar Laine sang the national anthem prior to the game … Announced paid attendance was 3,532.