ALAMEDA _ The Raiders have officially avoided double-digit losses heading into the regular-season finale, and while that may not sound like much, it is just the third time in the last 13 seasons they won’t be associated with the bottom feeders of the NFL.

General manager Reggie McKenzie is on record as a believer in building through the draft, using free agency only to cherry-pick a few players to fit in as needed.

Yet the Raiders, whether they go into the off-season at 7-9 or 8-8, can count McKenzie’s acumen at adding free agents in 2015 as a reason why things are looking up in Oakland or wherever it is the franchise rests its head next season.

The Raiders added eight unrestricted free agents last off-season, and McKenzie hit on at least five of them, a .625 percentage that any personnel executive would envy.

Former NFL executive and Hall of Fame inductee Bill Polian, in outlining the perils of free agency, makes two key points regarding the open market:

— Players are available because their own teams didn’t step up to sign them first.

— It often takes a year for a player to become acclimated to a new team, new systems of football and a new place to live.

As an immediate fix, free agency leaves a lot to be desired.

Ranking the free agents in terms of what they contributed to the Raiders with one game to play in 2015:

1) WR Michael Crabtree, 49ers — Originally signed to a one-year, $3.2 million contract plus incentives last May 30, Crabtree was locked up with a four-year, $34 million extension to stay with the Raiders.

With 82 receptions for 888 yards and eight touchdowns, Crabtree instantly gave second-year quarterback Derek Carr a reliable possession receiver. Unlike his tenure with the 49ers, Crabtree remained healthy, enabling him to be an active and enthusiastic participant in training camp as well as regular-season practices.

2) DT Dan Williams, Arizona — Sometimes the moves you can’t make pay off big. The Raiders made a serious run at Ndamukong Suh, a signing which would have restricted their ability to sign players.

The Raiders consolation prize was Williams, who was much cheaper at four years and $25 million with $15.2 million guaranteed. He grades out as one of the top run-stuffers in the NFL most weeks, according to Profootballfocus.com

3) C Rodney Hudson, Kansas City — The first move the Raiders made in free agency cost the most in terms of potential outlay and average salary. Hudson got $44.5 million over five years, with $12.65 guaranteed.

Hudson was slowed the second half of the season with a high ankle sprain that caused him to miss two games, but has proved to be an adept run-blocker and pass blocker when healthy.

4) LB Malcolm Smith, Seattle — A bargain at two years and $7 million with $3.75 million guaranteed, Smith went from playing sporadically with the Seahawks to playing more defensive snaps than anyone on the team and leading the Raiders in tackles.

Smith also had four sacks, and the forced fumble that helped turn the Chargers game around was representative of what he brings to the defense.

5) TE Lee Smith, Buffalo — Smith has just 12 catches for 70 yards and a touchdown, but that throwing him passes was never the plan. Smith is one of the NFL’s top in-line blockers at his position. He brought an element of toughness to the offensive line at coast of three years and $9.1 million with $3.1 million guaranteed.

6) LB Curtis Lofton, Atlanta: As the season evolved, Lofton’s playing time was reduced at the expense of younger, faster linebackers such as rookies Neiron Ball and Ben Heeney. Still useful in short yardage and goal line situations but a liability in pass coverage, Lofton signed a three-year, $18 million contract with $6.5 million guaranteed.

With salaries of $5.5 and $6 million over the next two seasons, and with the Raiders having the ability to walk away from the deal with no cap hit, Lofton could be in line for a release or salary reduction.

7) S Nate Allen, Philadelphia: The four-year, $23 million contract (with $6.9 million guaranteed) was considered a head-scratcher at the the time. Allen had a solid preseason, had an MCL strain in the season opener and went on injured reserve/designated for return.

When Allen returned, he struggled both in coverage and with his tackling. Allen is still on the 53-man roster after injuring his knee again. Allen is due salaries of $4.9 million, $5.85 million and $4.85 million over the next three years but like all of McKenzie’s deals, the heavy lifting was done in Year 1.

8) RB Roy Helu Jr., Washington: Signed to be a complementary back for two years and $4.1 million, Helu has just 14 rushes for 34 yards and seven receptions for 52 yards. He has been a healthy scratch in six of the last eight games.