Each of those six players has been invited to participate in the Pirates' Major League Spring Training.
Bautista had been the team's one arbitration-eligible player that the Pirates did not offer a contract to by the Dec. 12 non-tender deadline. The right-hander held a fairly significant role in the Pirates' bullpen during the final half of the season last year, but the Pirates did not want to be locked into the salary increase Bautista would have been in line for had he and the Pirates gone to arbitration. Bautista made $395,000 in 2008 and would likely have been given near double that had a Major League contract been tendered.
Still, by signing Bautista to a Minor League deal, the Pirates will give him a chance to compete for a bullpen spot out of Spring Training. After being acquired by the Pirates in June, Bautista made 35 relief appearances and allowed 28 earned runs in 41 1/3 innings. He struck out 34 and walked 28.
Bootcheck, who has spent his entire professional career with the Angels since being a first-round Draft selection in 2000, will also be given the chance to earn a spot in the Pirates' bullpen during Spring Training.
Bootcheck, 30, made 10 relief appearances for the Angels last season after dealing with elbow soreness. The right-hander allowed 18 earned runs, 12 walks and struck out 24 in 10 innings. He also pitched in 19 games for the Angels' Triple-A affiliate and finished with a 2.86 ERA there.
General manager Neal Huntington expressed little concern that Bootcheck's elbow issues from last season will be a lingering issue going into next year.
"We feel like he'll be ready to compete from Day 1 of Spring Training," Huntington said. "Our medical people signed off on him. We'll just monitor him more closely than everybody else."
The additions of Jones, Salazar and Phillips give the Pirates three potential bench options depending on how things play out during Spring Training.
After making his Major League debut with the Twins in 2007, Jones, 27, spent last year in Triple-A, where he hit .279, with 23 homers, 33 doubles and 92 RBIs as a first baseman and outfielder. He led the International League in total bases and finished second in extra-base hits.
"Jones is a guy whose bat we really like," Huntington said. "We feel like he could compete to be a bat off the bench."
Phillips, 31, gives the Pirates a versatile infield option, as he has experience playing first, second and third. He has spent parts of five seasons in the Majors, and split last year between the Mets and the Reds.
Phillips is a career .250 hitter in the Majors. He has 14 homers and 70 RBIs in 557 career big league at-bats.
Ramon Vazquez, who the Pirates recently signed to a two-year deal, and Luis Cruz have been the most likely to assume backup-infielder roles. However, Huntington said that Cruz's ability to also play the outfield would certainly allow for another backup infielder, like Phillips, to make the club out of Spring Training.
Huntington also added that this doesn't mean the club has shut the door on the possibility of Doug Mientkiewicz also returning. The club has spoken with Mientkiewicz's agent, though no contract has yet been offered as Mientkiewicz continues to explore other options.
The 28-year-old Salazar has spent the past two seasons in Arizona. He hit .211 with 12 RBIs in 128 at-bats -- almost all as a pinch-hitter -- in 2008.
Huntington emphasized that his search for a right-handed-hitting outfielder continues, even though the signing of the left-handed-hitting Salazar would give the Pirates a potential fourth-outfielder option. The Pirates are already likely to have an all left-handed-hitting outfield.
"Salazar is an interesting guy that, in a perfect world, would be right-handed," Huntington said. "But we feel like he can compete to make our club. He's a disciplined hitter who can get on base and he brings a little bit of a speed element to the game."
Mateo, 26, started the '08 season in the Cubs' farm system before signing with Pittsburgh as a Minor League free agent on May 4. He then pitched in 32 Double-A games for the Curve and finished 7-1 with a 2.12 ERA.
Jenifer Langosch is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.