Monday's international free-agent signing day ranks right there with the first day of the MLB Draft as far as importance for Major League clubs.
The rules and procedures are different and clubs don't all put the same emphasis on international scouting, especially in Latin America. The players are also younger than those drafted -- the best are usually just 16 years old -- and require more patience. But every international signing period represents a significant opportunity for a club to add young talent to their system.
AL East | AL Central | NL East | NL Central | NL West
Here are five prospects from the American League West who show the impact that international signings can have on a club.

Angels: SS Kevin Maitan (Dec. 5. 2017)
How he's doing: The Angels weren't the first to sign Maitan. The Braves signed him on July 2, 2016, but he was declared a free agent last winter by the Commissioner's Office as part of the Braves' punishment for international scouting violations. The Angels ended up signing him for $2.2 million and he is now their No. 2 prospect in their farm system, along with 78th overall by MLB Pipeline. He was a big addition to a depleted farm system, although right now he is playing in the Rookie-level Pioneer League. He is a switch-hitter with power from both sides.
ETA: Maitan is obviously just getting started but could move quickly if the bat shows up early. He may end up being a corner infielder, but he has a good feel for the game and the hitting ability to be a middle-of-the-order impact bat.

Astros: LHP Cionel Perez (Dec. 9, 2016).
How he's doing: With a small frame and a quick arm, the 22-year-old Cuban has excelled at Double-A Corpus Christi this year, going 5-1 with a 2.20 ERA and 71 strikeouts in 57 1/3 innings over his first 14 outings (10 starts). He throws in the low 90s with sink, and his slider and changeup have improved.
ETA: Perez's long-term future could be in the bullpen because of his stature and the Astros' wealth of starting pitching. It wouldn't be a surprise to see him in the big leagues later this year. If not, he's likely to compete for a roster spot in 2019.

Athletics: Lazaro "Lazarito" Armenteros (July 2, 2016)
How he's doing: Ranked No. 7 among A's prospects, Armenteros was assigned to Class A Short Season Beloit for the start of his first full professional season. He was riding a .289 average with four home runs when he suffered a quad injury that forced him to the seven-day disabled list earlier this month. The 19-year-old, signed by the A's for $3 million at the start of the 2016-17 international period, should be back in action next month.
ETA: Thought to be one of the most dynamic talents to come out of Cuba in recent years, Armenteros could move quickly through the A's system. It's far too early, however, to put a timetable on him. The outfielder is expected to remain in Beloit, before advancing to Class A Advanced Stockton in 2019. His skill set begs comparisons to a Cuban phenom familiar to A's fans: Yoenis Cespedes.

Mariners: Julio Rodriguez (signed July 2, 2017)
How he's doing: The 17-year-old outfielder from the Dominican Republic is a five-tool prospect who signed with the Mariners for a $1.75 million bonus last year and was immediately installed as Seattle's No. 4 prospect by MLB Pipeline. At 6-foot-3, 180 pounds, Rodriguez has intriguing size and raw power for a teenager, along with a strong arm and decent speed. Most scouts project him as a future right fielder with middle-of-the-order offensive potential.
ETA: If he progresses as hoped, the youngster could be ready to contribute to the Mariners in about four years. He'll be 21 in 2022.
Rangers: Leody Taveras (July 2, 2015)
How he's doing: Taveras remains the Rangers' No. 1 prospect and No. 30 overall by MLB Pipeline. He is still just 19 but holding his own with the Down East Wood Ducks in the Class A Advanced Carolina League. His outstanding speed and athleticism makes him well suited to play center field. He is a switch-hitter with speed and strike-zone control, while his power is still developing.
ETA: Next season will be a big one for Taveras as he closes in on making the crucial jump to Double-A. He has always been one of the youngest players at his level, so he has yet to have a dominating confidence-building season. But it is possible he could make his Major League debut in 2020 and be ready for a full-time job in '21.