Fund Russell 1000® Growth Index

Sector Weightings: Defines what % of each sector this fund holdscompared to its benchmark listed here.

QTD YTD

Portfolio Attribution: Describes how fund manager sector and stockweighting decisions affected returns.

Sector Attribution Details: Sector Fund Weight Q T D Y T D

Communication Services 12.03 -0.08 -0.21

Consumer Discretionary 13.62 -0.15 -0.46

Consumer Staples 4.70 0.08 -0.09

Energy 0.25 -0.01 0.15

Financials 2.87 -0.02 -0.24

Health Care 14.92 0.21 -0.50

Industrials 8.70 0.17 -0.14

Information Technology 39.41 -0.28 -0.26

Materials 0.90 0.07 -0.18

Real Estate 1.85 0.07 -0.10

Cash 0.35 -0.03 -0.09

Quarterly Portfolio Commentary:

Martin Poirier, CIMA Investment DirectorInvestment Experience: 19 Years

HIGHLIGHTS• The domestic large-cap growth asset class outperformed the large-capvalue asset class for the fourth quarter in a row. • All sectors of the index delivered positive returns for the quarter, withhealth care and information technology leading the way. • Weak stock selection detracted from the Fund’s relative performance,mainly attributed to weakness in the information technology sector.• Sector allocation was favorable in the quarter. Underweights to theweak performing real estate and industrial sectors helped performance,as did an overweight to the health care sector.

Fund Objective: This Fund seeks to create a diversified portfolio of equity securities in order to outperform the total return performance of itsbenchmark, the Russell 1000® Growth Index*.

The Fund is not promoted, sponsored, or endorsed by, nor in any way affiliated with Russell Investment Group (“Russell”). Russell is not responsible forand has not reviewed the Fund nor any associated literature or publications and Russell makes no representation or warranty, express or implied, as to theiraccuracy, or completeness, or otherwise. The Russell 1000® Growth Index and Russell® are trademarks of the Frank Russell Company.These materials and the platform of investments made available by MassMutual are offered without regard to the individualized needs of any plan, itsparticipants, or beneficiaries. These materials are not intended as impartial investment advice or to give advice in a fiduciary capacity to any plan.

NOT FDIC INSURED MAY LOSE VALUE NO BANK GUARANTEE

Quarterly Review

R5 SHARE CLASS TICKER: MPGSX

As of 12/31/2019

MassMutual Premier Disciplined Growth FundBarings LLC

Com

m. Services

Consumer Discr.

Consumer Staples

Energy

Financials

Health Care

Industrials

Information Tech.

Materials

Real Estate

Cash

0

10

20

30

40

Percent of P

ortfolio

Percent of P

ortfolio

Com

m. Services

Consumer Discr.

Consumer Staples

Energy

Financials

Health Care

Industrials

Information Tech.

Materials

Real Estate

Cash

-0.75

-0.50

-0.25

0.00

0.25

Value Added vs. Benchmark (%

)Value Added vs. Benchmark (%

)

*

Quarterly Portfolio Commentary:

The Russell 1000® Growth Index outperformed the Russell 1000® Value Index in the quarter as large-cap growth stocks continued to lead large-cap valuestocks in overall returns. Large-cap growth equities also outperformed their mid- and small-cap counterparts. All ten sectors delivered positive returns inthe period, with health care and information technology delivering the largest gains. As information technology and health care represent the largest twosectors, accounting for more than half of the index weight, their outperformance had significant impact on returns. The information technology sectormade the largest contribution to returns benefiting from strong price appreciation from both Microsoft and Apple, the two largest companies in the index.The health care sector delivered the second largest positive contribution as shares of health care providers and services, and biotechnology firms postedstrong share price gains. The troubled energy sector, the worst performing sector for the full year, delivered a respectable gain in the quarter as oil pricestrended higher in the quarter.

The Fund modestly lagged the Russell 1000 Growth Index for the quarter, with the information technology sector detracting the most from relativeresults. The Fund held an overweight position to several poor performing stocks in the sector. Top detractors were Oracle, a software and services firm,and International Business Machines (IBM), an information technology firm. Oracle fell in the quarter as the firm beat market expectations on earnings,but missed on revenue growth. While their cloud services business increased revenue modestly, the results was below projections. Shares of IBM declinedas the firm posted another quarter of revenue contraction. The company has been lowering full-year earnings estimates as its Global Technology Servicesunits has been challenged. Stock selection was also weak in the consumer discretionary sector, driven by the Fund’s overweight position in onlinemarketplace firm, eBay.Health care, the second largest sector weight for the Fund, had the most positive impact on quarterly performance. Both strong stock selection and anoverweight to the sector aided performance. Amgen, a leading biotechnology firm, was a top contributor. Shares were higher in the quarter as the firmannounced an investment in a Chinese drugmaker. Eli Lilly & Co, a pharmaceutical firm, was also a top contributor. The firm posted strong results drivenlargely by growth in newer medicines and effective cost management. Overweight positions to these stock was rewarded. Stock selection was alsopositive in consumer staples, led by Altria Group - the largest U.S. tobacco company. Shares were up in the quarter as the firm beat market earningsexpectations and announced further price increases on tobacco cigarettes.

TICKER: MPGSX Fund Inception: 12/19/2000Morningstar Category: Large Cap Growth

Average Annual Total Return

Q T D Y T D 1 Year 3 Year 5 Year 10 year

MassMutual Premier Disciplined Gr R5 10.52% 33.45% 33.45% 18.06% 12.81% 14.48%

Russell 1000® Growth Index 10.62% 36.39% 36.39% 20.49% 14.63% 15.22%

Category Average Return -- -- 31.90% 18.09% 12.10% 13.40%

Category Rank -- -- 38 51 43 26

# of Funds in Category -- -- 1,360 1,218 1,086 811

Performance shown is for class R5 shares. Gross expenses = 0.62%, Net expense = 0.62%. Max Sales charge for R5 is 0%Performance shown is past performance. Past performance does not guarantee future results . You can lose money, includingloss of pr incipal , by invest ing in this fund. Investors should careful ly consider investment objectives, r isks , charges andexpenses. This and other important information is contained in the fund prospectuses and summary prospectuses, which can beobtained from www.massmutualfunds.com and should be read careful ly before invest ing. A l ist of the Fund’s holdings can alsobe obtained from www.massmutualfunds.com. Current performance may be lower or higher than return data quoted herein. Formore current information, including month-end performance, please cal l 1-866-444-2601. You cannot invest directly in an index.Investment Risks - The Fund’s Princ ipa l R isks include - Cash Position Risk, Derivatives Risk, Equity Securities Risk, Frequent Trading/Portfolio TurnoverRisk, Growth Company Risk, Indexing Risk, Large Company Risk, Liquidity Risk, Management Risk, Market Risk, Valuation Risk. Please refer to the summaryprospectus (a copy can be obtained by sending an email to fundinfo@massmutual.com) for more information on the specific risks.The Morningstar percenti le ranking is based on the fund’s total-return percenti le rank relat ive to al l funds that have the samecategory for the same t ime period. The highest (or most favorable) percentile rank is 1%, and the lowest (or least favorable) percentile rank is 100%.Morningstar total return includes both income and capital gains or losses and is not adjusted for sales charges. © 2020 Morningstar, Inc. All RightsReserved. The information contained herein: (1) is proprietary to Morningstar and/or its content providers; (2) may not be copied or distributed; and (3) isnot warranted to be accurate, complete or timely. Neither Morningstar nor its content providers are responsible for any damages or losses arising from anyuse of this information.

MassMutual Premier Disciplined Growth Fund

1

Quarter to Date:

Top 5 Contributors F u n dW e i g h t

AbsoluteReturn*

Portfol ioContr ibut ion

Apple Inc 8.82 31.50 2.53

Microsoft Corp 8.49 13.82 1.16

Facebook Inc A 3.68 15.26 0.54

UnitedHealth Group Inc 1.42 35.80 0.43

Amgen Inc 1.54 25.40 0.36

 

Top 5 Detractors F u n dW e i g h t

AbsoluteReturn*

Portfol ioContr ibut ion

Boeing Co 0.63 -13.89 -0.09

Oracle Corp 1.36 -3.30 -0.06

International BusinessMachines Corp 0.79 -6.74 -0.05

Cisco Systems Inc 2.09 -2.21 -0.05

The Home Depot Inc 0.93 -5.28 -0.04

Year to Date:

Top 5 Contributors F u n dW e i g h t

AbsoluteReturn*

Portfol ioContr ibut ion

Apple Inc 7.68 88.97 6.19

Microsoft Corp 7.71 57.57 4.07

Facebook Inc A 3.34 56.57 1.41

Amazon.com Inc 5.38 23.03 1.22

Alphabet Inc A 3.04 28.18 0.95

Top 5 Detractors F u n dW e i g h t

AbsoluteReturn*

Portfol ioContr ibut ion

Cisco Systems Inc 1.11 -11.19 -0.36

Herbalife Nutrition Ltd 0.20 -19.13 -0.12

Urban Outfitters Inc 0.12 -31.36 -0.10

Sinclair Broadcast Group Inc 0.07 -37.97 -0.09

Oracle Corp 0.78 19.33 -0.09

RS9093b RS-45364-06

Portfolio Holdings:

 Fund Weightings are shown as an average for the time period.*Absolute Return is the return that an asset achieves over a certain period of time. This measure looks at the appreciation or depreciation (expressed as apercentage) that a holding achieves over a given period of time.For a complete listing of fund holdings, visit massmutualfunds.com or please call 1-866-444-2601. The mention of individual stocks and other securities inthis document does not constitute investment advice.

© 2020 Massachusetts Mutual Life Insurance Company (MassMutual®), Springfield, MA. All rights reserved. www.MassMutual.com Principal Underwriter:MML Distributors, LLC. (MMLD) Member FINRA and SIPC (www.FINRA.org and www.SIPC.org) MMLD is a subsidiary of Massachusetts Mutual LifeInsurance Company, 100 Bright Meadow Blvd., Enfield, CT 06082. Investment advisory services provided to the Funds by MML Investment Advisers, LLC.

MassMutual Premier Disciplined Growth Fund

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