Why do I get a segmentation fault with this char?

So I'm starting to learn C, tried to make a little program to learn about structures. It asks two "players" to enter their name and age, and then displays it back.

When I run it, I get a segmentation fault after entering the second player's last name. I don't get why.

I tried to run it in gdb and got the following message :

Program received signal SIGSEGV, Segmentation fault.
0x00007ffff7e5288c in _IO_vfscanf () from /lib/x86_64-linux-gnu/libc.so.6

Here is my code, struct.c :

#include "struct.h"
#include <stdio.h>
#include <stdlib.h>

int main(int argc, char *argv[]) {
  Person player[1];
  int i = 0;

  for (i = 0; i < 2; i++) {
    printf("\n=== Player %d ===\n", i+1);
    printf("First name : ");
    scanf("%s", player[i].firstName);
    printf("Last name : ");
    scanf("%s", player[i].lastName);
    printf("Age : ");
    scanf("%d", &player[i].age);
  }

  for (i = 0 ; i < 2; i++) {
    printf("\n=== Player %d ===\n", i+1);
    printf("%s %s, %d years old", player[i].firstName, player[i].lastName, player[i].age);
  }

  return 0;
}

And here is the header, struct.h :

#ifndef DEF_STRUCT
#define DEF_STRUCT
#define CHAR_SIZE 100

typedef struct Person Person;
struct Person {
  char firstName[CHAR_SIZE];
  char lastName[CHAR_SIZE];
  int age; 
};

#endif

Thanks!