BRADENTON, Fla. -- Pedro Alvarez, after the prescribed weekend off to quiet his barking left knee, was back in the Pirates' starting lineup at third base for Monday night's exhibition against Baltimore.

Alvarez has been virtually guaranteed to still be there for the April 5 regular-season inaugural game against Philadelphia, since general manager Neal Huntington has dismissed any suggestion that his Spring Training woes had the club considering sending him to Triple-A. And the Phillies that day will be starting a right-hander in the person of Roy Halladay.

Beyond that, in the short-term, who knows? Huntington qualified his unwavering vote of confidence in Alvarez by conceding that he could be excused against certain left-handers at the start of the season.

That is where the situation, and especially the way it impacts roster decisions, gets very tricky. Within the first week of the season, the Pirates will face five southpaws, including some of the toughest in the National League.

If Alvarez does sit out those starts, third base would have to be manned by someone other than Casey McGehee -- who would likely be at first base, with Garrett Jones also not starting against the left-handers. Either of the candidates to be the alternate third baseman -- Josh Harrison or Yamaico Navarro -- would also provide the only middle-infield insurance.

If only one of them makes the club, having him start at the hot corner would leave the Bucs without a replacement at shortstop or at second base.

In the short term, the solution could come from the Pirates' ability to go with a four-man rotation, which would create temporary roster room for both Harrison and Navarro to make the 25-man squad, as well as Matt Hague, a first baseman who has also gotten acquainted with third, but will likely only play there in an emergency.

Those five lefties -- Cliff Lee, Cole Hamels, Clayton Kershaw, Ted Lilly and Chris Capuano -- are all lined up to face the Bucs prior to April 15, when the No. 5 starter's spot first comes up.

In the long term, the ideal solution is for Alvarez to begin raking so convincingly that you can't get him out of the lineup with a crowbar.

Clouding the decisions facing manager Clint Hurdle and Huntington is the fact that, as a group, the third-base contenders have been the offensive stars of the Pirates' exhibition campaign. They were most responsible for the Bucs having entered Monday play leading both the National League and the Grapefruit League with a .289 team batting average.

Entering Monday night's game:

• Hague was batting .417 (15-for-36) and leading the club with four homers.
• Harrison was batting .500 (14-for-28) and leading the club with seven doubles that put his OPS at 1.369.
• Navarro was batting .364 with a team-high 16 hits.

Meanwhile, Alvarez faced Baltimore's Tommy Hunter on Monday night batting .133, with four hits and 13 strikeouts in 30 at-bats.

Hunter gave everyone fits, blanking the Pirates on one hit through six. Still, Alvarez's continuing troubles seemed to stand out, as he struck out in both of his at-bats against the right-hander, then grounded out against lefty Zach Phillips in his last at-bat.

However, Alvarez's struggles are being viewed through the same Spring Training prism as the other third basemen's production.

"We don't want to respond over-the-top to good or bad," Huntington told reporters on Sunday. "Certainly, there are some areas of concern [with Alvarez]. There's been some positive signs as well."

A four-man rotation would be a very interim situation. When the Pirates' staff goes full strength with five starters and seven relievers, it will leave room for only two of Hague, Navarro and Harrison.

Harrison is the only "incumbent" among them, getting his big-league baptism with the Pirates last season when Alvarez was hurt, and making a good impression in 65 games (he batted .272 with 16 extra-base hits).

Yet Harrison and Hague are the two with options remaining. However, Hague appears to be in his own category because of his power, a commodity in short supply for the Bucs.

"It'd be easy to start thinking about what could happen, but I can't worry about it," Harrison said. "All I can be concerned with is my effort, my attitude and my work.

"I'm very pleased with my spring. I've definitely gotten my chances, at bat and in the field. I've gotten reps at as many positions as possible," added Harrison, who hopes to have added to his value by proving adept at short, a position he had not played since his junior year at the University of Cincinnati.

The competition for those infield jobs has been hot, and will simmer for eight more days. They're all in this together.

"We're all having fun. We feed off each other and pull for each other," said Harrison, acknowledging that team leadership may not look forward to tough decisions, but loves having to make them. "It's better to have too many options than not enough."