Chicago Cubs Prospect Profile: Riley Thompson Quietly Lighting Up South Bend

When I picked six not-so-obvious Cubs pitching prospects to watch for the 2019 season, I didn’t realize just how quickly one of them would be very obvious. Atop the list was Riley Thompson, an 11th round pick out of Louisville last summer who could be named the Cubs minor league pitcher of the month for April. He made four starts (19 IP) with a 1.42 ERA, striking out 16 and walking only five (four of which came in his last start).

Thompson had served as Louisville’s closer, logging just seven starts. His 6+ ERA during his junior year didn’t really bode well for his success as a pro, but Thompson was still developing and the Cubs picked him based on potential. Having a 95 mph heater helps. 

The Cubs began to stretch Thompson out at Eugene last summer, pushing his starts from 2 to 5 innings over a six week period. Along with way, his ERA went from a high of 9.00 down to 2.84 as he totaled 16 strikeouts in 19 innings. He showed good command of his fastball, a result of a great deal of focus. In film study, I notice he threw 80% fastballs the first time through the order.

The next step was to work on commanding his secondaries, most notably his slider. You can see the wildness of the breaking ball here, but also notice Thompson’s quiet delivery. 

As a result of his form, minor tweaks could have a huge impact on Thompson’s delivery. That’s part of the reason he came in at No. 27 on MLB Pipeline’s top 30 Cubs prospect list despite being relatively unheralded. It is interesting that the Cubs have gone all in with him as a starter at this point, but that’s a reflection of the organization’s more aggressive developmental philosophy.

Thompson’s fastball velocity fluctuated during his final season at Louisville, dipping to the low 90s at times and topping out at 98 mph at others, and his curveball was similarly inconsistent. As a pro, he worked at 93-98 mph and hit 100 with his heater and spun some well-above-average curves with power and depth. He even showed promise with a changeup he didn’t utilize much in college.


After battling the strike zone at Louisville, Thompson displayed better control after Chicago cleaned up his lower half in his delivery. He still has a long ways to go to prove he can remain healthy, maintain quality stuff and locate his pitches. While the Cubs will continue to develop him as a starter, he could move quickly as a reliever.

This year at South Bend, Thompson is mixing in a beautiful 12-to-6 curve that has a nice sharp break to it. He has also displayed good stamina, starting out throwing 91-92 mph and getting stronger as the game continues.

Here’s Thompson talking about how his success and what he is working on.

Now that May is here, Thompson is more than likely going to continue to work on his secondaries and his third pitch, a changeup. The way he is getting arm-side run on his fastball and a nice bite on his curve, things are looking up for the young 22-year-old.

Ed. note: Thompson is starting for the SB Cubs Saturday night against the Clinton LumberKings and our Todd Johnson will be there to cover it. 

Back to top button