Does It Always Seem Like Someone's Making Their MLB Debut?

Here's a look at year-by-year MLB debut totals since 2000, with a quick look back at 1950-1990

Does it always seem like you’re reading about or watching a game where someone’s making their MLB debut? Whether it’s a top prospect that gets the call, a minor league journeyman finally getting his chance, or a random reliever getting thrown into the mix because of injuries or success in the minors, (at least to me) it seems like someone’s always making their debut. How does that compare to the past?

Every season around this time (perhaps in July if I’m bored and my mind wanders) I get thinking about how many have made their MLB debut for the year and how that compares to recent years. For these comparisons, I will be using the almighty Baseball Reference, and will focus more on the last quarter century (2000-present). The year-to-year totals have been strikingly consistent. Almost too consistent. I won’t list out every single year but will group by 10 seasons and then see how we’re looking for 2020-2024.

From 2000-2009 the average yearly total of debuts was 208, with the lowest coming in 2003 with 182 and the most coming in 2008 with 238 debuts. As you may have guessed, the league average has only increased from there. From 2010-2019 there were 2,394 debuts, giving us an average of 239 per season in that time. The lowest total debuts over this span was in 2012 when there was just 206, with the most being in 2017 with 262.

Now 2020-2024 obviously isn’t a full 10-year block to go by, but I’ll list these seasons out year-by-year because this is where things start to get more interesting.

2020 (shortened COVID season): 212

2021: 265

2022: 303(!)

2023: 261

2024 (so far): 186

We’re already at 1,227 debuts over (almost) 5 full seasons, giving us a season average of 245. If history is any indicator, it appears that we’ve still got roughly 60-75 more debuts left this season. Now I will point out that recently, MLB rosters have been bumped to 26, and on days of a doubleheader teams are afforded a 27th man. These changes have allowed for some more flexibility and potential for guys to make their debut. We also had the 2020 COVID-shortened season with the 60-man player pool along with the taxi squad (remember that phrase?). I’ve always found it interesting how with the 2020 “COVID season” where teams played just a 60-game regular season, we still saw a pretty sizeable amount of debuts relative to the seasons sandwiched around it. Otherwise, I’m sure we would’ve easily seen 250+ debuts that season by the way things have been trending.

Let’s hop in the DeLorean and go back a bit in time for some fun with history (I’m just going to do a quick look here at the decade marks for a total debut comparison to give an idea of how times have changed):

1950: 104

1960: 104

1970: 140

1980: 145

1990: 169

2000: 204

I may do a deeper dive on this in the future, but for now, as it relates to MLB debuts, it really gives a quick visual of how baseball has changed over the years and how it compares to now. Also, for another visual example, take last year’s 261 debuts and divide that by 6 full months of the regular season (April-September); that’s about 44 MLB debuts per month!

It’s also worth noting that the average MLB age in 2024, thus far, is 28.6 years old. 20 years ago in 2004, the average MLB age was 29.2. As older players retire, and with injuries and top prospects moving quicker through the minors than we’ve seen in the past, I imagine this debut trend will steadily rise - and slowly chip away at the league average age. There’s obviously many variables to all this, but it’s interesting how there’s been a relatively consistent range of year-to-year MLB debut totals. It’s a bit random, but it’s been a trend I’ve kept an eye on the last few years after I started thinking about it. For me, it also paints a fun visual of people reading the newspaper back in the 70’s and 80’s (relative to their time compared to years prior), possibly wondering the same thing, “why does it always seem like someone’s making their debut?”