Drew Pomeranz-to-Red Sox deal could be win-win for both teams

Stark: Red Sox paid a big price for Pomeranz (1:01)

Jayson Stark reacts to the Red Sox's acquisition of Drew Pomeranz for 18-year-old Anderson Espinoza, who Stark says has been compared to Pedro Martinez. (1:01)

From 2011 to 2015, Drew Pomeranz posted a 4.60 ERA as a part-time starter. The San Diego Padres acquired him this past offseason from the Oakland A's -- for the small price of Yonder Alonso -- and gave him a chance to start on a regular basis, and Pomeranz made the All-Star team after going 8-7 with a 2.47 ERA in the first half.

The Padres decided to sell high on the 27-year-old left-hander, trading him to the Boston Red Sox in a deal that reportedly netted teenage right-hander Anderson Espinoza, viewed as one of the top pitching prospects in the minors.

Quick thoughts:

1. It's no surprise that Red Sox chief executive Dave Dombrowski would deal from his deep farm system. He was hired with win-now orders, and since the Red Sox possess the most potent lineup in the American League -- they've scored 5.63 runs per game, with only the Baltimore Orioles (at 5.08) also above 5.0 per game -- the Red Sox needed to supplement a rotation that ranks ninth in the AL with a 4.72 ERA. The back of the rotation, in particular, has struggled behind David Price, Rick Porcello and All-Star Steven Wright. Eduardo Rodriguez had a 10.03 ERA in his five starts since June 1; Clay Buchholz, after a stint in the bullpen, has a 6.14 ERA in three starts since returning to the rotation; Sean O'Sullivan was given four starts. Joe Kelly, back in the minors trying to get healthy, is headed to the bullpen.

2. Pomeranz's season may be a surprise, but his numbers so far aren't necessarily a fluke. He ranks seventh among NL starters in strikeout rate, sixth in "well-hit average" (percentage of balls defined as hit hard) and second among all MLB starters in OPS allowed. His ground ball rate is a tick above average. The one number that looks ripe for regression is the batting average allowed: .184, best in the National League, one point better than Clayton Kershaw's .185. There's also the concern that Pomeranz doesn't have elite command, averaging 3.6 walks per nine, and he's moving into a division with a lot of patient hitters and power hitters.

The one big change in Pomeranz's game: He has added a cutter this year, giving him a third offering to go with his fastball and curveball. That's why Oakland's Billy Beane traded him; he viewed Pomeranz simply as a reliever due to that two-pitch arsenal. Pomeranz learned the cutter in spring training from a minor leaguer named Travis Higgs. Jeff Sullivan of FanGraphs wrote about this the other day. Back in spring training, Pomeranz explained what happened. "I just asked, 'What was that?'" Pomeranz said. "He showed me the grip and where to apply the pressure."

3. Pomeranz is not just a rental. He's not eligible for free agency until after 2018, so the Red Sox control him for two more seasons. While he's arbitration-eligible, he was making $1.35 million this year, so he won't take a huge leap in salary next year.

4. Twitter! Twitter went nuts, with comments like this one:

I mean, sure, that could happen, but those kinds of trade results are obviously extreme, and baseball front offices are smarter than they were 25 years ago. On the other hand, the prospect evaluators love Espinoza. Keith Law just ranked him No. 14 on his midseason top 50 list, writing, "He'll be up to 99 mph but sits comfortably at 94-95 with both the changeup and curveball flashing plus, with the changeup being the better of the two pitches. There aren't many comparisons for Espinoza because so few pitchers have done what he has done with this kind of stuff at 18, but the fact that Pedro Martinez comps aren't laughable is a pretty good indicator of what Espinoza could be."

At 18, Espinoza is the youngest pitcher in the South Atlantic League, although he also has a 4.62 ERA despite allowing just two home runs in 76 innings. Yes, he could turn into John Smoltz, but a lot could go wrong between now and his rise to Hall of Famer. It's worth noting this:

So while the Red Sox are banking on Pomeranz's improvement being a real thing, the Padres are taking on risk, as well.

5. That's what makes this deal so much fun. If the Red Sox win the World Series and Espinoza turns into Pedro Martinez (OK, let's be fair, there will not be another Pedro Martinez), are the Red Sox -- front office and fans -- happy with the results? You tell me.

6. The big mistake here: The Red Sox not re-signing Rich Hill. He finished last September with Boston with a flourish, but the Sox let him walk. So not signing Hill cost them one of baseball's top prospects. The ripple effect of decisions also is fun here. (Especially since it was the A's who traded Pomeranz but signed Hill, who is likely the next starting pitcher to be traded.)