The Double-A Reading duo each have 22 homers and 66 RBIs after driving in four runs each Thursday in the team's 13-5 win over Erie.
Cozens, who hit a three-run homer in the seventh, went 2-for-4 with a double, while Hoskins did all his damage in one swing, an eighth-inning grand slam.
The rest of the best performances from top prospects Thursday:
• No. 5 overall prospect Dansby Swanson (Braves' No. 1) hit his fourth triple of the season as part of a 4-for-5 performance for Double-A Mississippi in a 6-5 win. Swanson fell into a bit of a slump in the middle of the month, but has closed June strong, collecting multiple hits in four of his past seven games.
• Astros top prospect Alex Bregman (No. 18 overall) and Teoscar Hernandez (Astros' No. 24) combined to go 8-for-11 with a homer and six RBIs in their Triple-A debuts. Bregman went 4-for-5 with a pair of doubles and three RBIs. Hernandez finished 4-for-6 with three RBIs, a homer and his first triple of the year in Fresno's 23-3 rout of Salt Lake.
• Yankees No. 2 prospect Aaron Judge (No. 27 overall) only got two at-bats for Triple-A Scranton/Wilkes-Barre in its 8-1 win, but he made them count. Judge extended his hitting streak to eight games with a three-run double in the eighth inning and finished the game 1-for-2.
• No. 28 overall prospect Brett Phillips (Brewers' No. 2) collected two doubles and three RBIs, going 2-for-4 in Double-A Biloxi's win over Birmingham.
• Royals No. 1 prospect Raul Mondesi (No. 32 overall) went 2-for-5 with three RBIs in Class A Advanced Wilmington's 7-4 win and showed both power and speed as he doubled and hit his sixth homer of the year and first since returning from suspension.
• Pirates No. 3 prospect Josh Bell (No. 44 overall) helped lead Triple-A Indianapolis to a win with a homer and three RBIs in a 2-for-3 performance. Bell has five hits in his last six at-bats and is hitting .327.
• No. 46 overall prospect Dominic Smith (Mets' No. 1) continues to rake for Double-A Binghamton, going 2-for-4 with a double and RBI. The first baseman has hits in eight of his last 10 games and has three homers and eight RBIs in that span.
• Cubs No. 4 prospect Duane Underwood (No. 68 overall) got back on track and helped Double-A Tennessee win in 10 innings, 2-1, as he scattered four hits over six innings. The 21-year-old gave up four runs in four innings in his previous start. Although he only struck out two, Underwood was in complete control all game, throwing 56 of his 87 pitches for strikes, walking just one and allowing one unearned run.
• Braves No. 4 prospect Kolby Allard (No. 80 overall) lowered his ERA to 1.80 after navigating his way through six scoreless innings for Rookie-level Danville in its 3-0 win. The 18-year-old left-hander has held opponents without an earned run in two of his last three starts.
"I threw the ball well," Allard told MiLB.com. "I established the fastball early and worked both sides of the plate, in and out, and then basically worked off of that with everything else. When you can do that, everything falls into place. I started mixing in my curveball and changeup as the game went on and it worked out well."
• Luis Lugo (Indians' No. 25) tossed 6 2/3 scoreless innings for Class A Advanced Lynchburg in its 9-1 win over Salem. The young left-hander walked two and gave up just four hits, which was his first scoreless start of the year.
• Marlins' No. 20 prospect Avery Romero notched his first three-hit game with Class A Advanced Jupiter, going 3-for-3 with a run scored in a 3-2 win.
• Mets' No. 19 prospect Gregory Guerrero is heating up in the Dominican Summer League. The 17-year-old shortstop is 7-for-8 with two RBIs over the past two days for the DSL Mets and hitting .317 through 21 games.
• There's a reason Adam Walker (Twins' No. 10) has "walkoff" in his Twitter handle. The powerful outfielder is a home run threat every at-bat and he proved it once again, hitting a walk-off grand slam for Triple-A Rochester.
• Another day, another two hits for Dustin Fowler (Yankees' No. 6). After going 2-for-4 with three RBIs, Fowler has two hits in each of his past three games for Double-A Trenton.