Brock Holt celebrates after knocking in the game-winning run for the Red Sox against the Chicago White Sox at Fenway Park on July 9. (Photo by Jim Rogash/Getty Images)

By Johnny Carey, CBS Boston

BOSTON (CBS) — With Opening Day still six days away, Red Sox manager John Farrell has already made his first major lineup adjustment.

On Tuesday, Farrell announced that Brock Holt will start in left field against right-handed pitching over Rusney Castillo.

Holt, who was an all-star last season, gets the nod over a man the Red Sox signed to a $72.5 million contract.

Considering Farrell has already announced that Chris Young will start in left field against lefties, and that he envisions Jackie Bradley Jr. alongside Mookie Betts as an everyday outfielder, Castillo projects to be a very expensive bench player.

An argument against the move could cite Holt’s value in a super-utility role as well as his lack of playing time in left field. Both of these concerns are valid; however, what’s most important about Farrell’s decision is the message it sends to the 2016 Boston Red Sox.

Starting Holt shows that Farrell is willing to make whatever move he deems necessary to win now, regardless of a player’s pay-grade.

And really, isn’t that what a manager is supposed to do?

There’s less uncertainty with Holt than Castillo, and in order to shake off the cobwebs of back-to-back last place finishes, Farrell wants as little uncertainty in the lineup as possible.

This isn’t to say that everything is a guarantee with Holt, who only started only eight games in left field last season. He saw the majority of his time at second base, and spent most of his outfield innings in right.

Still, Holt has shown to be effective (at least in the first half of the season) regardless of his position, and quite frankly, Castillo hasn’t done anything to indicate that he’s ready to be a starter in the major leagues yet.

Despite being the clear front-runner for the job all offseason, Castillo has done himself no favors in a spring training which has seen him hit .227, with zero home runs, 1 RBI and a woeful .542 OPS.

Spring training numbers shouldn’t be the end-all-be-all of player evaluation, but the reality is that Castillo didn’t fare particularly well last season either, hitting .253 with five home runs and 29 RBI in 80 games.

Castillo needed to show at least some signs of improvement, and he was unable to do so. For a manager who can’t afford a bad start to the season, that clearly makes Holt the more attractive option.

Even just the indication that Farrell will be managing more aggressively this season could be a very good thing for the 2016 Red Sox.

When the Red Sox won the World Series in 2013, Farrell stressed competition based upon results, and whoever was playing the best at the time earned the most innings.

A combination of competition and job insecurity seemed to light the fire under Farrell’s players that helped produce a championship lineup.

The hope is that the same strategy works to ignite Castillo, because even in relegating the outfielder to the bench, the Red Sox have not given up on him. For $72.5 million over 90 career games played, they really can’t afford to.

It’s not shocking news, but at the same time, Farrell’s decision to start Holt is a good sign that the team won’t sit around and wait for results from its high-paid players this season.

Johnny Carey is a senior at Boston College. You can find him on Twitter @JohnnyHeights.