Mets first baseman Pete Alonso has had the National League Rookie of the Year Award pretty much sewn up for weeks as he constructs one of the most impressive debut seasons in history.

Meanwhile, the American League also has a clear frontrunner in Astros designated hitter Yordan Alvarez. That he made his Major League debut 74 days after Alonso has only made his meteoric rise that much more impressive.

Alonso and Alvarez are the runaway leaders in MLB.com's latest Rookie of the Year poll. Alvarez received all 35 first-place votes in the AL; Alonso received 31 in the NL.

As for the rest of the field, a pair of Blue Jays have moved up in the AL. Third baseman Vladimir Guerrero Jr. jumped from fifth to second, while teammate Bo Bichette, who has played just 32 games, cracked the top five for the first time (fifth).

In the NL, Braves pitcher Mike Soroka is back in second place for the first time since week two after jumping Padres shortstop Fernando Tatis Jr., who is out for season.

Alonso has finished first in all five NL polls, while Alvarez was first for the second straight time.

Alonso is leading all rookies in homers (43), RBIs (102), extra-base hits (72), total bases (292), runs (83) and walks (63). With a month to go, his 72 extra-base hits are the 18th-highest total for a rookie.

Since his debut in June, Alvarez is tied for fourth among AL hitters with 22 home runs, fourth in RBIs (63) and third in OBP (.413) and OPS (1.084).

He was the AL Rookie of the Month for June and July, and led AL rookies in August in an assortment of categories: home runs (nine), RBIs (26) and OPS (1.095).

MLB.com reporters were asked to rank their top three choices in each league, with five points for a first-place vote, three for second place and one for third.

Here’s a breakdown of the leaders:

American League

Alvarez (35 first-place votes): He set an MLB record for most RBIs in his first 45 games with 51, breaking Ted Williams' record of 47 in 1939. With his home run Monday, he tied the Astros' rookie record of 22 set by Carlos Correa in 2015, and he has 22 multihit games in his first 66 games.

Guerrero Jr.: He’s hit .350 with 10 doubles, seven home runs and 14 walks in his last 37 games to raise his batting average 40 points to .278. Among AL rookies, he’s first in hits (107) and doubles (23), and second in extra-base hits (39) and walks (42). His 12 games of at least three hits are tops among AL rookies.

Brandon Lowe: He’s not expected to play again this season because of a right shin contusion and left quadriceps strain. At the time of his injury on July 2, he led the Rays with 16 home runs and 49 RBIs and was the clear AL Rookie of the Year Award frontrunner. He was also named to the AL All-Star team. Ten of his 16 home runs tied games or gave the Rays a lead. His eight go-ahead homers were tied for third most in the AL.

Others receiving votes: John Means, Bichette, Luis Arraez.

National League

Alonso (31 first-place votes): He’s tied for the MLB lead with 21 tying or go-ahead home runs, and his 28 go-ahead RBIs are tied for second in the Majors. His 26 multi-RBI games are tied for the 11th-most in the Majors, and he has 12 games with at least three RBIs (tied for fifth in MLB). He’s reached base in 29 straight games.

Soroka (four first-place votes): His 2.44 ERA at the beginning of play on Monday was the second best by a Braves rookie in the live-ball era (1920) and the lowest by an MLB rookie since Jose Fernandez had a 2.19 ERA in 28 starts in 2013. He snapped an eight-game winless streak (a span in which he posted a 2.81 ERA) on Monday by tossing five innings of three-run ball against the Blue Jays. Among pitchers with at least 20 starts, his 2.72 ERA in games his team has lost is the lowest in the Majors (Sonny Gray of the Reds is second at 3.15).

Tatis Jr.: His rookie season ended after 84 games due to a back injury, but he was everything the Padres hoped he’d be with a .969 OPS and 22 homers, 13 doubles and six triples.

Other receiving votes: Bryan Reynolds, Christian Walker, Mike Yastrzemski.