Profar was ranked No. 1, while infielder Mike Olt was No. 22, infielder Luis Sardinas was No. 84, Buckel was No. 87, catcher Jorge Alfaro was No. 88 and Perez was No. 95.
Profar, 19, moved to the top spot after hitting .281 with 76 runs scored, 26 doubles, seven triples, 14 home runs, 62 RBIs and 16 stolen bases at Double-A Frisco last season. He had a .368 on-base percentage and a .452 slugging percentage. He was on the Texas League All-Star team and voted by the managers as the top defensive shortstop in the league.
Profar was called up to the Rangers in September and was 3-for-17 in nine games, including a home run in his first Major League at-bat. He was the first Rangers player to hit a home run in his first at-bat and the third youngest in Major League history.
"What I've seen is quite impressive," Rangers manager Ron Washington said. "The game of baseball does not scare him, and that's a tough attribute for a young kid to already have, and he certainly has it. The game doesn't scare him. And because the game doesn't scare him, that means he won't be taken aback by adversity. Because in this game, it's full of adversity. And if you can't handle adversity, then this game will eat you up.
"I don't think the game will eat him up, especially how he feels about the game of baseball. And experienced players, but not only players but coaching staff that he will have around him, we will not let him fail. He's quite an impressive kid."
The annual ranking of baseball's biggest and brightest young talent is assembled by MLB.com's Draft and prospect expert Jonathan Mayo, who compiles input from industry sources, including scouts and scouting directors. It is based on analysis of players' skill sets, upsides, closeness to the Majors and potential immediate impact to their teams. The list, which is one of several prospect rankings on MLB.com's Prospect Watch, only includes players with rookie status in 2013.
To qualify for rookie status, a player must not have exceeded 130 at-bats or 50 innings pitched in the Major Leagues, or accumulated more than 45 days on the active roster of a Major League club or clubs during the 25-player-limit period, excluding time on the disabled list or in military service.
Olt was the 2012 winner of the Tom Grieve Award as the Rangers Minor League Player of the Year. He spent four months with Frisco and hit .282 with 17 doubles, 28 home runs, 82 RBIs and a .579 slugging percentage. He still ended up leading the Texas League in home runs and slugging percentage despite being called up to the Rangers at the beginning of August.
Olt played in 16 games with the Rangers and was 5-for-16 while playing third, first and the outfield. He missed significant time with severe inflammation in his right foot.
Sardinas, 19, was signed three years ago out of Venezuela and spent last season at Class A Hickory. He played in 96 games and hit .291 as a switch-hitter, with 65 runs scored, 14 doubles, two triples, two home runs, 30 RBIs and 32 stolen bases. He had a .346 on-base percentage, a .356 slugging percentage and also batted .326 in the second half of the season.
Sardinas' career has been off to a slow start because of a series of injuries, but he did play in 11 games during the Arizona Fall League and batted .318 with a .375 on-base percentage and a .455 slugging percentage. He was the youngest player in the league.
Buckel was the Rangers' second-round pick in the 2010 First-Year Player Draft out of Royal (Calif.) High and was the 2012 winner of the Nolan Ryan Award as the organization's Top Minor League Pitcher. Buckel, 20, went 10-8 with a 2.49 ERA with 159 strikeouts in 144 innings and 26 games while splitting time between Class A Myrtle Beach and Frisco. He was 5-5 with a 3.78 ERA in 10 starts and three relief appearances for Frisco.
Alfaro, 19, has a chance to be one of the outstanding catching prospects in the game if he can stay healthy. A native of Colombia, he played in 74 games at Hickory and hit .261 with 40 runs scored, 21 doubles, five triples, five home runs, 34 RBIs and a .430 slugging percentage in 300 plate appearances. But he played just 29 games behind the plate while dealing with hamstring and shoulder injuries.
Alfaro played in 19 games during the Puerto Rican Winter League and hit .292 with two home runs and 10 RBIs in 65 at-bats. He had a .446 slugging percentage. He is also considered an above-average defensive player.
Perez, 21, dropped from No. 43 in the last Top 100 list after going 7-6 with a 4.25 ERA in 21 starts and one relief appearance at Triple-A Round Rock. In 127 innings, he allowed 122 hits and 56 walks while striking out 69. He also made six starts and six relief appearances for the Rangers, going 1-4 with a 5.45 ERA. In 38 innings, he allowed 47 hits and 15 walks while striking out 25.
Perez still finished the 2012 season as the Rangers' fifth starter and will go into Spring Training as one of several candidates for that spot.