According to what expected goals (xG) tell us, perhaps the race for the league's top scorer was closer than it should've been.

This metric tells us the number of goals a player would be expected to score based on the chances he finds – each shot is assigned a value from zero to one. And in the case of Castellanos, he not only tied D.C. United's Ola Kamara with 19 goals (and won the boot via the assists tiebreaker), but could've had more than 22 goals with something closer to league-average luck.

Here are five facts about the 2021 MLS regular-season leaders in expected goals.

Five key facts

1. TATY WELL DESERVING: Castellanos finished top both the MLS xG list at 22.64 and the Golden Boot rankings (19g/8a), which should end any dispute over whether the award found its rightful owner this season.

2. BAD NEWS BERIC: After making a run at the 2020 Golden Boot, Chicago Fire FC's Robert Beric underperformed his 12.65 xG more than any other MLS player in the top 25 of xG this season, scoring only eight times. Beric won't be back in Chicago in 2022, and the Designated Player's struggles impacted another postseason-less season in the Windy City.

3. MVP CONTENDERS: Sporting Kansas City's Daniel Salloi and Nashville SC's Hany Mukhtar are two strong considerations for the 2021 Landon Donovan MLS MVP award. They're also among the players to overperform their xG totals the most in terms of actual goals scored.

4. DARKHORSE DUO: Looking for an MLS Cup longshot? You might consider the New York Red Bulls or Minnesota United FC. They're the only teams to have multiple players in MLS' top 25 who underperformed their xG total. RBNY have Patryk Klimala and Fabio, while MNUFC have Adrien Hunou and Robin Lod.

5. KREILACH DRAMA: One of Decision Day's most dramatic moments was when Real Salt Lake attacker Damir Kreilach netted a 95th-minute winner at SKC to seal his team's Audi MLS Cup Playoffs spot. Turns out that was indicative of a larger trend, with Kreilach most over-performing his xG value (+4.97). He finished the regular season with 16g/9a in 33 games.

BONUS: The New England Revolution are the only team with two top-10 players in the xG chart: Gustavo Bou and Adam Buksa. Unsurprisingly, the Supporters' Shield winners had a league-leading 65 goals while setting a new single-season points record (73).

Here are the top 25 xG performers in the 2021 MLS regular season, with data sourced from Opta:

2021 MLS regular season xG leaders
Player
xG
Goals
xG difference
1. Valentin Castellanos (NYC)
22.64
19
-3.64
2. Adam Buksa (NE)
19.07
16
-3.07
3. Ola Kamara (DC)
17.46
19
+1.54
4. Raul Ruidiaz (SEA)
16.4
17
+0.6
5. Chicharito (LA)
14.79
17
+2.21
6. Felipe Mora (POR)
12.89
11
-1.89
7. Robert Beric (CHI)
12.65
8
-4.65
8. Gustavo Bou (NE)
12.47
15
+2.53
9. Cristian Arango (LAFC)
12.31
14
+1.69
10. Patryk Klimala (RBNY)
11.99
8
-3.99
11. Kacper Przybylko (PHI)
11.88
12
+0.12
12. Josef Martinez (ATL)
11.57
12
+0.43
13. Hany Mukhtar (NSH)
11.53
16
+4.47
14. Daniel Salloi (SKC)
11.18
16
+4.82
15. Gonzalo Higuain (MIA)
11.09
12
+0.91
16. Damir Kreilach (RSL)
11.03
16
+4.97
17. CJ Sapong (NSH)
10.81
12
+1.19
18. Brenner (CIN)
10.73
8
-2.73
19. Adrien Hunou (MIN)
10.64
7
-3.64
20. Brian White (VAN)
10.49
12
+1.51
21. Fabio (RBNY)
10.26
7
-3.26
22. Rubio Rubin (RSL)
10.08
8
-2.08
23. Cristian Dajome (VAN)
9.95
10
+0.05
24. Ricardo Pepi (DAL)
9.86
13
+3.14
25. Robin Lod (MIN)
9.77
9
-0.77