SANTA CLARA -- The 49ers hardly made fireworks Thursday in the first round of the NFL draft. But they did manage to light up a small sparkler. Or perhaps it was a fizzy Roman candle, though not a fizzy Roman candle previously unknown to mankind.

"This was a scenario we hoped to see pan out," said general manager Trent Baalke after he made his strategic move, which occurred fairly early in the evening.

Baalke used two of the team's 13 lower picks to work a deal for the Dallas Cowboys' 18th spot and move up to select Eric Reid, a safety from LSU.

At first blush, you can give the 49ers a thumbs up on the selection. Reid was among the country's best defensive players last season.

Yet when trying to translate with certainty how draft picks will pan out when they pull on real NFL equipment, never forget those important words on the manufacturer's label: Safety not guaranteed.

Especially with safeties.

Moving up to choose Reid made sense. The 49ers do need someone at that position to eventually -- or very soon -- replace departed Pro Bowl free agent Dashon Goldson. So why not Reid? He played in America's most superior college conference, the SEC. He therefore faced the country's best college offenses on a weekly basis. Reid did well enough to be named an All-American.

"He plays big in the big games," said 49ers coach Jim Harbaugh, who added Reid "has the ability to be" a starter this season.

Of course, that's been said before about other defensive backs -- with mixed results. If you grade Baalke on the curve, he's done well a talent evaluator. He was part of the team braintrust that chose Goldson as a fourth-rounder in the 2007 draft. Yet the same braintrust badly misfired three years ago when Baalke and then-G.M. Scot McCloughan chose another safety among the top 50 picks -- USC's Taylor Mays in the second round (overall No. 49).

Very quickly, the 49ers must have regretted that choice. Mays played sparingly and was traded after his rookie year to Cincinnati for a seventh-round pick. He has started three games over the past two seasons for the Bengals, making little impact.

Reid is a different variety of safety than Mays, who was known as a center fielder type who lusted after big hits -- but too often took the wrong angle and whiffed or was penalized for an illegal one. Reid, at 6-foot-1 and 213 pounds, has a reputation as more of a wrap-up type tackler. That's significant at a time the NFL just passed a rule about banning crown-of-helmet contact.

Baalke said it's always a challenge for rookie defenders to "learn the angles at the NFL level" and adjust to the pro game's faster speed. But he liked the way Reid played back in the deep secondary at LSU and also could move up in the box to stifle runners at the scrimmage line.

"We feel good about his ability to insert and play a physical brand of football," Baalke said.

The 49ers must feel very, very good about that. The other top-tier safety available Thursday was Texas' Kenny Vaccaro, who was selected 15th by New Orleans. The 49ers obviously possessed enough trade booty to move up and take Vaccaro if they wished. Instead, they passed and waited three more picks before making the deal to nab Reid.

Afterward, Harbaugh confirmed Reid "was our top-rated safety" and that his selection was "a unanimous decision."

Reid, in a conference call with Bay Area reporters, sounded like the usual eager rookie trying to impress. He has some familiarity with the Bay Area because his mother is a traveling nurse who has worked in San Jose from time to time. Reid also must be a smart guy. He was recruited by Stanford when Harbaugh was the head coach.

"I think I'm a very cerebral player," Reid said on the telephone, which you can assess as either cockiness or confidence.

For now, let's go with confidence. Reid appears to be a good 49ers fit. But you never know for sure about any NFL rookie until he lines up on the same field with a bunch of NFL veterans and feels full NFL contact. That won't happen for real until summertime. Lest we forget: Last year's top pick, wide receiver A.J. Jenkins, arrived with good reviews yet barely stepped onto the field during the 2012 season.

So, yes, lighting a sparkler is permissible after picking Reid. But hold off on larger pyrotechnics until September. Plus, with Baalke still holding 11 picks for the later draft rounds Friday and Saturday, further firecrackers could be in the picture.

Contact Mark Purdy at mpurdy@mercurynews.com. Follow him on Twitter at twitter.com/MercPurdy.

Inside
49ers give up Nos. 31 and 74 to move up 13 spots and select LSU's Eric Reid. Page 4